Vulnerability-Lookup

CVE-2026-63075 (GCVE-0-2026-63075)

Vulnerability from cvelistv5 – Published: 2026-08-25 13:00 – Updated: 2026-08-25 14:36

Title

QUIC ACK-only Packet Retention Can Cause Memory Exhaustion

Summary

Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedly sends ack-eliciting packets while not acknowledging ACK-only responses, the QUIC stack can retain ACK-only packet metadata for the lifetime of the connection. Impact summary: A remote peer that can complete a QUIC handshake can cause connection-scoped memory growth which may lead to Denial of Service through memory exhaustion, especially with sustained traffic or many concurrent QUIC connections. CWE: CWE-770: Allocation of Resources Without Limits or Throttling Description: When the OpenSSL QUIC stack sends an ACK-only packet, there is no requirement by the QUIC protocol that the peer will acknowledge that ACK-only packet (i.e. it is itself not ack-eliciting). However, the OpenSSL implementation stores the metadata about the ACK frames regardless. In and of itself that's ok, but if a malicious peer establishes a connection, and then drives the connection such that ACK-only packets are forced from the OpenSSL implementation peer (i.e., by sending numerous PING frames), and then withholding any subsequent acks for ack-eliciting data, like legitimate data, said malicious peer can force inappropriate memory growth on the OpenSSL peer, potentially leading to a Denial of Service. The fix is to ensure that we account for the transmission of the ACK-only packet in the packet histories high and low watermark without actually storing the ACK-only packet metadata itself. FIPS impact: no The OpenSSL FIPS module is not affected as the QUIC code is outside the FIPS module boundary.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-25 14:36 UTC

CWE

CWE-770 - Allocation of Resources Without Limits or Throttling

Assigner

openssl mitre root

References

5 references

URL	Tags
https://openssl-library.org/news/secadv/20260825.txt	vendor-advisory
https://github.com/openssl/openssl/commit/7308946…	patch
https://github.com/openssl/openssl/commit/bf84721…	patch
https://github.com/openssl/openssl/commit/7c98d79…	patch
https://github.com/openssl/openssl/commit/c902e5f…	patch

Impacted products

1 product

Vendor	Product	Version	CPE status
OpenSSL	OpenSSL	Affected: 4.0.0 , < 4.0.2 (semver) Affected: 3.6.0 , < 3.6.4 (semver) Affected: 3.5.0 , < 3.5.8 (semver) Affected: 3.4.0 , < 3.4.7 (semver)	guessed

Date Public

2026-08-25 11:36

Credits

Opal Wright (Trail of Bits) Neil Horman

Show details on NVD website

JSON

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However, the OpenSSL\\nimplementation stores the metadata about the ACK frames regardless.\\nIn and of itself that\u0027s ok, but if a malicious peer establishes a connection, and\\nthen drives the connection such that ACK-only packets are forced from the \\nOpenSSL implementation peer (i.e., by sending numerous PING frames),\\nand then withholding any subsequent acks for ack-eliciting data, like\\nlegitimate data, said malicious peer can force inappropriate memory growth\\non the OpenSSL peer, potentially leading to a Denial of Service.\\n\\nThe fix is to ensure that we account for the transmission of the ACK-only\\npacket in the packet histories high and low watermark without actually storing\\nthe ACK-only packet metadata itself.\\n\\nFIPS impact: no\\nThe OpenSSL FIPS module is not affected as the QUIC code is\\noutside the FIPS module boundary.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedly\u003cbr\u003esends ack-eliciting packets while not acknowledging ACK-only responses, the\u003cbr\u003eQUIC stack can retain ACK-only packet metadata for the lifetime of the\u003cbr\u003econnection.\u003cbr\u003e\u003cbr\u003eImpact summary: A remote peer that can complete a QUIC handshake can\u003cbr\u003ecause connection-scoped memory growth which may lead to Denial of Service\u003cbr\u003ethrough memory exhaustion, especially with sustained traffic or many concurrent\u003cbr\u003eQUIC connections.\u003cbr\u003e\u003cbr\u003eCWE: CWE-770: Allocation of Resources Without Limits or Throttling\u003cbr\u003e\u003cbr\u003eDescription: When the OpenSSL QUIC stack sends an ACK-only packet,\u003cbr\u003ethere is no requirement by the QUIC protocol that the peer will acknowledge\u003cbr\u003ethat ACK-only packet (i.e. it is itself not ack-eliciting). However, the OpenSSL\u003cbr\u003eimplementation stores the metadata about the ACK frames regardless.\u003cbr\u003eIn and of itself that\u0027s ok, but if a malicious peer establishes a connection, and\u003cbr\u003ethen drives the connection such that ACK-only packets are forced from the \u003cbr\u003eOpenSSL implementation peer (i.e., by sending numerous PING frames),\u003cbr\u003eand then withholding any subsequent acks for ack-eliciting data, like\u003cbr\u003elegitimate data, said malicious peer can force inappropriate memory growth\u003cbr\u003eon the OpenSSL peer, potentially leading to a Denial of Service.\u003cbr\u003e\u003cbr\u003eThe fix is to ensure that we account for the transmission of the ACK-only\u003cbr\u003epacket in the packet histories high and low watermark without actually storing\u003cbr\u003ethe ACK-only packet metadata itself.\u003cbr\u003e\u003cbr\u003eFIPS impact: no\u003cbr\u003eThe OpenSSL FIPS module is not affected as the QUIC code is\u003cbr\u003eoutside the FIPS module boundary.\", \"base64\": false}]}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-770\", \"description\": \"CWE-770 Allocation of Resources Without Limits or Throttling\"}]}], \"providerMetadata\": {\"orgId\": \"3a12439a-ef3a-4c79-92e6-6081a721f1e5\", \"shortName\": \"openssl\", \"dateUpdated\": \"2026-08-25T13:00:04.752Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-63075\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-08-25T14:36:51.928Z\", \"dateReserved\": \"2026-07-15T13:10:26.188Z\", \"assignerOrgId\": \"3a12439a-ef3a-4c79-92e6-6081a721f1e5\", \"datePublished\": \"2026-08-25T13:00:04.752Z\", \"assignerShortName\": \"openssl\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}

alsa-2026:67154

Vulnerability from osv_almalinux

Published

2026-09-14 00:00

Modified

2026-09-15 08:31

Summary

Important: openssl security, bug fix, and enhancement update

Details

OpenSSL is a toolkit that implements the Secure Sockets Layer (SSL) and Transport Layer Security (TLS) protocols, as well as a full-strength general-purpose cryptography library.

Security Fix(es):

openssl: OpenSSL: Denial of Service via unbounded memory growth in QUIC server (CVE-2026-14456)
openssl: QUIC server may trigger double free when processing INITIAL packet (CVE-2026-18798)
openssl: heap buffer overflow in CMS key unwrapping (CVE-2026-63072)
openssl: invalid pointer dereference in CMP server via crafted protectionAlg (CVE-2026-63076)
openssl: RPK server signature algorithm selection can dereference a missing certificate (CVE-2026-14457)
openssl: excessive memory use buffering DTLS records for a future epoch (CVE-2026-54874)
openssl: untrusted sender DN used as format string in CMP response validation (CVE-2026-63073)
openssl: CMP indefinite cache growth of ExtraCerts (CVE-2026-63074)
openssl: QUIC ACK-only packet retention can cause memory exhaustion (CVE-2026-63075)

Bug Fix(es) and Enhancement(s):

openssl: HollowByte remote memory-exhaustion DoS fix may be missing [AlmaLinux 10.2.z] (JIRA:AlmaLinux-212362)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

References

URL

Type

	https://access.redhat.com/errata/RHSA-2026:67154	ADVISORY
	https://access.redhat.com/security/cve/CVE-2026-14456	REPORT
	https://access.redhat.com/security/cve/CVE-2026-14457	REPORT
	https://access.redhat.com/security/cve/CVE-2026-18798	REPORT
	https://access.redhat.com/security/cve/CVE-2026-54874	REPORT
	https://access.redhat.com/security/cve/CVE-2026-63072	REPORT
	https://access.redhat.com/security/cve/CVE-2026-63073	REPORT
	https://access.redhat.com/security/cve/CVE-2026-63074	REPORT
	https://access.redhat.com/security/cve/CVE-2026-63075	REPORT
	https://access.redhat.com/security/cve/CVE-2026-63076	REPORT
	https://bugzilla.redhat.com/2515348	REPORT
	https://bugzilla.redhat.com/2517559	REPORT
	https://bugzilla.redhat.com/2517560	REPORT
	https://bugzilla.redhat.com/2517561	REPORT
	https://bugzilla.redhat.com/2517562	REPORT
	https://bugzilla.redhat.com/2517564	REPORT
	https://bugzilla.redhat.com/2517565	REPORT
	https://bugzilla.redhat.com/2517566	REPORT
	https://bugzilla.redhat.com/2517570	REPORT
	https://errata.almalinux.org/10/ALSA-2026-67154.html	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "AlmaLinux:10",
        "name": "openssl"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:3.5.8-1.el10_2.alma.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "AlmaLinux:10",
        "name": "openssl-devel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:3.5.8-1.el10_2.alma.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "AlmaLinux:10",
        "name": "openssl-libs"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:3.5.8-1.el10_2.alma.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "AlmaLinux:10",
        "name": "openssl-perl"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:3.5.8-1.el10_2.alma.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "OpenSSL is a toolkit that implements the Secure Sockets Layer (SSL) and Transport Layer Security (TLS) protocols, as well as a full-strength general-purpose cryptography library.  \n\nSecurity Fix(es):  \n\n  * openssl: OpenSSL: Denial of Service via unbounded memory growth in QUIC server (CVE-2026-14456)\n  * openssl: QUIC server may trigger double free when processing INITIAL packet (CVE-2026-18798)\n  * openssl: heap buffer overflow in CMS key unwrapping (CVE-2026-63072)\n  * openssl: invalid pointer dereference in CMP server via crafted protectionAlg (CVE-2026-63076)\n  * openssl: RPK server signature algorithm selection can dereference a missing certificate (CVE-2026-14457)\n  * openssl: excessive memory use buffering DTLS records for a future epoch (CVE-2026-54874)\n  * openssl: untrusted sender DN used as format string in CMP response validation (CVE-2026-63073)\n  * openssl: CMP indefinite cache growth of ExtraCerts (CVE-2026-63074)\n  * openssl: QUIC ACK-only packet retention can cause memory exhaustion (CVE-2026-63075)\n\n\nBug Fix(es) and Enhancement(s):  \n\n  * openssl: HollowByte remote memory-exhaustion DoS fix may be missing [AlmaLinux 10.2.z] (JIRA:AlmaLinux-212362)\n\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.\n",
  "id": "ALSA-2026:67154",
  "modified": "2026-09-15T08:31:16Z",
  "published": "2026-09-14T00:00:00Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:67154"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-14456"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-14457"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-18798"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-54874"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-63072"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-63073"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-63074"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-63075"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-63076"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2515348"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517559"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517560"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517561"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517562"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517564"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517565"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517566"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517570"
    },
    {
      "type": "ADVISORY",
      "url": "https://errata.almalinux.org/10/ALSA-2026-67154.html"
    }
  ],
  "related": [
    "CVE-2026-14456",
    "CVE-2026-18798",
    "CVE-2026-63072",
    "CVE-2026-63076",
    "CVE-2026-14457",
    "CVE-2026-54874",
    "CVE-2026-63073",
    "CVE-2026-63074",
    "CVE-2026-63075"
  ],
  "summary": "Important: openssl security, bug fix, and enhancement update"
}

alsa-2026:67165

Vulnerability from osv_almalinux

Published

2026-09-14 00:00

Modified

2026-09-15 08:35

Summary

Important: openssl security, bug fix, and enhancement update

Details

OpenSSL is a toolkit that implements the Secure Sockets Layer (SSL) and Transport Layer Security (TLS) protocols, as well as a full-strength general-purpose cryptography library.

Security Fix(es):

openssl: OpenSSL: Denial of Service via unbounded memory growth in QUIC server (CVE-2026-14456)
openssl: QUIC server may trigger double free when processing INITIAL packet (CVE-2026-18798)
openssl: heap buffer overflow in CMS key unwrapping (CVE-2026-63072)
openssl: invalid pointer dereference in CMP server via crafted protectionAlg (CVE-2026-63076)
openssl: RPK server signature algorithm selection can dereference a missing certificate (CVE-2026-14457)
openssl: excessive memory use buffering DTLS records for a future epoch (CVE-2026-54874)
openssl: untrusted sender DN used as format string in CMP response validation (CVE-2026-63073)
openssl: CMP indefinite cache growth of ExtraCerts (CVE-2026-63074)
openssl: QUIC ACK-only packet retention can cause memory exhaustion (CVE-2026-63075)

Bug Fix(es) and Enhancement(s):

openssl: HollowByte remote memory-exhaustion DoS fix may be missing [AlmaLinux 9.8.z] (JIRA:AlmaLinux-232828)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

References

URL

Type

	https://access.redhat.com/errata/RHSA-2026:67165	ADVISORY
	https://access.redhat.com/security/cve/CVE-2026-14456	REPORT
	https://access.redhat.com/security/cve/CVE-2026-14457	REPORT
	https://access.redhat.com/security/cve/CVE-2026-18798	REPORT
	https://access.redhat.com/security/cve/CVE-2026-54874	REPORT
	https://access.redhat.com/security/cve/CVE-2026-63072	REPORT
	https://access.redhat.com/security/cve/CVE-2026-63073	REPORT
	https://access.redhat.com/security/cve/CVE-2026-63074	REPORT
	https://access.redhat.com/security/cve/CVE-2026-63075	REPORT
	https://access.redhat.com/security/cve/CVE-2026-63076	REPORT
	https://bugzilla.redhat.com/2515348	REPORT
	https://bugzilla.redhat.com/2517559	REPORT
	https://bugzilla.redhat.com/2517560	REPORT
	https://bugzilla.redhat.com/2517561	REPORT
	https://bugzilla.redhat.com/2517562	REPORT
	https://bugzilla.redhat.com/2517564	REPORT
	https://bugzilla.redhat.com/2517565	REPORT
	https://bugzilla.redhat.com/2517566	REPORT
	https://bugzilla.redhat.com/2517570	REPORT
	https://errata.almalinux.org/9/ALSA-2026-67165.html	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "AlmaLinux:9",
        "name": "openssl"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:3.5.8-1.el9_8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "AlmaLinux:9",
        "name": "openssl-devel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:3.5.8-1.el9_8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "AlmaLinux:9",
        "name": "openssl-libs"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:3.5.8-1.el9_8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "AlmaLinux:9",
        "name": "openssl-perl"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1:3.5.8-1.el9_8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "OpenSSL is a toolkit that implements the Secure Sockets Layer (SSL) and Transport Layer Security (TLS) protocols, as well as a full-strength general-purpose cryptography library.  \n\nSecurity Fix(es):  \n\n  * openssl: OpenSSL: Denial of Service via unbounded memory growth in QUIC server (CVE-2026-14456)\n  * openssl: QUIC server may trigger double free when processing INITIAL packet (CVE-2026-18798)\n  * openssl: heap buffer overflow in CMS key unwrapping (CVE-2026-63072)\n  * openssl: invalid pointer dereference in CMP server via crafted protectionAlg (CVE-2026-63076)\n  * openssl: RPK server signature algorithm selection can dereference a missing certificate (CVE-2026-14457)\n  * openssl: excessive memory use buffering DTLS records for a future epoch (CVE-2026-54874)\n  * openssl: untrusted sender DN used as format string in CMP response validation (CVE-2026-63073)\n  * openssl: CMP indefinite cache growth of ExtraCerts (CVE-2026-63074)\n  * openssl: QUIC ACK-only packet retention can cause memory exhaustion (CVE-2026-63075)\n\n\nBug Fix(es) and Enhancement(s):  \n\n  * openssl: HollowByte remote memory-exhaustion DoS fix may be missing [AlmaLinux 9.8.z] (JIRA:AlmaLinux-232828)\n\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.\n",
  "id": "ALSA-2026:67165",
  "modified": "2026-09-15T08:35:13Z",
  "published": "2026-09-14T00:00:00Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:67165"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-14456"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-14457"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-18798"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-54874"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-63072"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-63073"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-63074"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-63075"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-63076"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2515348"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517559"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517560"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517561"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517562"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517564"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517565"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517566"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2517570"
    },
    {
      "type": "ADVISORY",
      "url": "https://errata.almalinux.org/9/ALSA-2026-67165.html"
    }
  ],
  "related": [
    "CVE-2026-14456",
    "CVE-2026-18798",
    "CVE-2026-63072",
    "CVE-2026-63076",
    "CVE-2026-14457",
    "CVE-2026-54874",
    "CVE-2026-63073",
    "CVE-2026-63074",
    "CVE-2026-63075"
  ],
  "summary": "Important: openssl security, bug fix, and enhancement update"
}

CERTFR-2026-AVI-1079

Vulnerability from certfr_avis - Published: 2026-08-26 - Updated: 2026-08-26

De multiples vulnérabilités ont été découvertes dans OpenSSL. Elles permettent à un attaquant de provoquer un déni de service à distance et un contournement de la politique de sécurité.

Solutions

Se référer au bulletin de sécurité de l'éditeur pour l'obtention des correctifs (cf. section Documentation).

Impacted products

Vendor	Product	Description
OpenSSL	OpenSSL	OpenSSL versions 3.6.x antérieures à 3.6.4
OpenSSL	OpenSSL	OpenSSL versions 3.4.x antérieures à 3.4.7
OpenSSL	OpenSSL	OpenSSL versions 3.5.x antérieures à 3.5.8
OpenSSL	OpenSSL	OpenSSL versions 3.0.x antérieures à 3.0.22
OpenSSL	OpenSSL	OpenSSL versions 1.0.2x antérieures à 1.0.2zr
OpenSSL	OpenSSL	OpenSSL versions 1.1.1x antérieures à 1.1.1zi
OpenSSL	OpenSSL	OpenSSL versions 4.0.x antérieures à 4.0.2

References

Title

Publication Time

FKIE_CVE-2026-63075

Vulnerability from fkie_nvd - Published: 2026-08-25 13:19 - Updated: 2026-09-11 21:17

Severity

7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Summary

References

URL	Tags
openssl-security@openssl.org	https://github.com/openssl/openssl/commit/7308946576b12e64b8be53bcf0a120354b2b42bc	Patch
openssl-security@openssl.org	https://github.com/openssl/openssl/commit/7c98d79738549df92868e7dd9be4bbf061eed709	Patch
openssl-security@openssl.org	https://github.com/openssl/openssl/commit/bf84721c2548351176e367e6de505792f0118dc6	Patch
openssl-security@openssl.org	https://github.com/openssl/openssl/commit/c902e5f16d6a9e130e96d3ca6d8f64d71652e393	Patch
openssl-security@openssl.org	https://openssl-library.org/news/secadv/20260825.txt	Vendor Advisory

Impacted products

Vendor	Product	Version
openssl	openssl	*
openssl	openssl	*
openssl	openssl	*
openssl	openssl	*

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "OpenSSL",
          "vendor": "OpenSSL",
          "versions": [
            {
              "lessThan": "4.0.2",
              "status": "affected",
              "version": "4.0.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.6.4",
              "status": "affected",
              "version": "3.6.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.5.8",
              "status": "affected",
              "version": "3.5.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.4.7",
              "status": "affected",
              "version": "3.4.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "openssl-security@openssl.org"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "216D6529-561A-4684-A886-50954FBEBFB2",
              "versionEndExcluding": "3.4.7",
              "versionStartIncluding": "3.4.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "C5BB9E95-09B6-4163-B51C-D62B528A04DA",
              "versionEndExcluding": "3.5.8",
              "versionStartIncluding": "3.5.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "B1416826-F2F1-4EA8-9FB2-A56B0DA923C1",
              "versionEndExcluding": "3.6.4",
              "versionStartIncluding": "3.6.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "63B8F45B-E44F-481C-815D-AF9CA89C48F6",
              "versionEndExcluding": "4.0.2",
              "versionStartIncluding": "4.0.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedly\nsends ack-eliciting packets while not acknowledging ACK-only responses, the\nQUIC stack can retain ACK-only packet metadata for the lifetime of the\nconnection.\n\nImpact summary: A remote peer that can complete a QUIC handshake can\ncause connection-scoped memory growth which may lead to Denial of Service\nthrough memory exhaustion, especially with sustained traffic or many concurrent\nQUIC connections.\n\nCWE: CWE-770: Allocation of Resources Without Limits or Throttling\n\nDescription: When the OpenSSL QUIC stack sends an ACK-only packet,\nthere is no requirement by the QUIC protocol that the peer will acknowledge\nthat ACK-only packet (i.e. it is itself not ack-eliciting). However, the OpenSSL\nimplementation stores the metadata about the ACK frames regardless.\nIn and of itself that\u0027s ok, but if a malicious peer establishes a connection, and\nthen drives the connection such that ACK-only packets are forced from the \nOpenSSL implementation peer (i.e., by sending numerous PING frames),\nand then withholding any subsequent acks for ack-eliciting data, like\nlegitimate data, said malicious peer can force inappropriate memory growth\non the OpenSSL peer, potentially leading to a Denial of Service.\n\nThe fix is to ensure that we account for the transmission of the ACK-only\npacket in the packet histories high and low watermark without actually storing\nthe ACK-only packet metadata itself.\n\nFIPS impact: no\nThe OpenSSL FIPS module is not affected as the QUIC code is\noutside the FIPS module boundary."
    }
  ],
  "id": "CVE-2026-63075",
  "lastModified": "2026-09-11T21:17:05.403",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-63075",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-08-25T14:36:48.832724Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-08-25T13:19:26.413",
  "references": [
    {
      "source": "openssl-security@openssl.org",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/openssl/openssl/commit/7308946576b12e64b8be53bcf0a120354b2b42bc"
    },
    {
      "source": "openssl-security@openssl.org",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/openssl/openssl/commit/7c98d79738549df92868e7dd9be4bbf061eed709"
    },
    {
      "source": "openssl-security@openssl.org",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/openssl/openssl/commit/bf84721c2548351176e367e6de505792f0118dc6"
    },
    {
      "source": "openssl-security@openssl.org",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/openssl/openssl/commit/c902e5f16d6a9e130e96d3ca6d8f64d71652e393"
    },
    {
      "source": "openssl-security@openssl.org",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://openssl-library.org/news/secadv/20260825.txt"
    }
  ],
  "sourceIdentifier": "openssl-security@openssl.org",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-770"
        }
      ],
      "source": "openssl-security@openssl.org",
      "type": "Secondary"
    }
  ]
}

GHSA-CJ75-R57J-R5V8

Vulnerability from github – Published: 2026-08-25 15:32 – Updated: 2026-08-25 15:32

Details

Impact summary: A remote peer that can complete a QUIC handshake can cause connection-scoped memory growth which may lead to Denial of Service through memory exhaustion, especially with sustained traffic or many concurrent QUIC connections.

CWE: CWE-770: Allocation of Resources Without Limits or Throttling

Description: When the OpenSSL QUIC stack sends an ACK-only packet, there is no requirement by the QUIC protocol that the peer will acknowledge that ACK-only packet (i.e. it is itself not ack-eliciting). However, the OpenSSL implementation stores the metadata about the ACK frames regardless. In and of itself that's ok, but if a malicious peer establishes a connection, and then drives the connection such that ACK-only packets are forced from the OpenSSL implementation peer (i.e., by sending numerous PING frames), and then withholding any subsequent acks for ack-eliciting data, like legitimate data, said malicious peer can force inappropriate memory growth on the OpenSSL peer, potentially leading to a Denial of Service.

The fix is to ensure that we account for the transmission of the ACK-only packet in the packet histories high and low watermark without actually storing the ACK-only packet metadata itself.

FIPS impact: no The OpenSSL FIPS module is not affected as the QUIC code is outside the FIPS module boundary.

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-63075"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-25T13:19:26Z",
    "severity": "HIGH"
  },
  "details": "Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedly\nsends ack-eliciting packets while not acknowledging ACK-only responses, the\nQUIC stack can retain ACK-only packet metadata for the lifetime of the\nconnection.\n\nImpact summary: A remote peer that can complete a QUIC handshake can\ncause connection-scoped memory growth which may lead to Denial of Service\nthrough memory exhaustion, especially with sustained traffic or many concurrent\nQUIC connections.\n\nCWE: CWE-770: Allocation of Resources Without Limits or Throttling\n\nDescription: When the OpenSSL QUIC stack sends an ACK-only packet,\nthere is no requirement by the QUIC protocol that the peer will acknowledge\nthat ACK-only packet (i.e. it is itself not ack-eliciting). However, the OpenSSL\nimplementation stores the metadata about the ACK frames regardless.\nIn and of itself that\u0027s ok, but if a malicious peer establishes a connection, and\nthen drives the connection such that ACK-only packets are forced from the \nOpenSSL implementation peer (i.e., by sending numerous PING frames),\nand then withholding any subsequent acks for ack-eliciting data, like\nlegitimate data, said malicious peer can force inappropriate memory growth\non the OpenSSL peer, potentially leading to a Denial of Service.\n\nThe fix is to ensure that we account for the transmission of the ACK-only\npacket in the packet histories high and low watermark without actually storing\nthe ACK-only packet metadata itself.\n\nFIPS impact: no\nThe OpenSSL FIPS module is not affected as the QUIC code is\noutside the FIPS module boundary.",
  "id": "GHSA-cj75-r57j-r5v8",
  "modified": "2026-08-25T15:32:59Z",
  "published": "2026-08-25T15:32:58Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-63075"
    },
    {
      "type": "WEB",
      "url": "https://github.com/openssl/openssl/commit/7308946576b12e64b8be53bcf0a120354b2b42bc"
    },
    {
      "type": "WEB",
      "url": "https://github.com/openssl/openssl/commit/7c98d79738549df92868e7dd9be4bbf061eed709"
    },
    {
      "type": "WEB",
      "url": "https://github.com/openssl/openssl/commit/bf84721c2548351176e367e6de505792f0118dc6"
    },
    {
      "type": "WEB",
      "url": "https://github.com/openssl/openssl/commit/c902e5f16d6a9e130e96d3ca6d8f64d71652e393"
    },
    {
      "type": "WEB",
      "url": "https://openssl-library.org/news/secadv/20260825.txt"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

MSRC_CVE-2026-63075

Vulnerability from csaf_microsoft - Published: 2026-08-27 01:11 - Updated: 2026-09-13 01:50

Summary

QUIC ACK-only Packet Retention Can Cause Memory Exhaustion

Scope

1 vulnerability in this advisory, including CVE-2026-63075.

CVE-2026-63075

7.5 (High)


                
                  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Fixed: 1 product Known affected: 6 products Known not affected: 1 product

Open the full advisory

OPENSUSE-SU-2026:11623-1

Vulnerability from csaf_opensuse - Published: 2026-08-27 00:00 - Updated: 2026-09-16 20:25

Summary

libopenssl-3-devel-3.5.3-8.1 on GA media

Severity

Moderate

Scope

11 vulnerabilities in this advisory, including CVE-2026-63075.

CVE-2026-63075

5.3 (Medium)


                
                  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Recommended: 40 products

Open the full advisory

OPENSUSE-SU-2026:21744-1

Vulnerability from csaf_opensuse - Published: 2026-09-02 15:55 - Updated: 2026-09-16 20:47

Summary

Security update for openssl-3

Severity

Important

Scope

11 vulnerabilities in this advisory, including CVE-2026-63075.

CVE-2026-63075

5.3 (Medium)


                
                  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Recommended: 19 products

Open the full advisory

RHSA-2026:59635

Vulnerability from csaf_redhat - Published: 2026-08-25 21:50 - Updated: 2026-09-14 07:58

Summary

Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update

Severity

Moderate

Scope

8 vulnerabilities in this advisory, including CVE-2026-63075.

CVE-2026-63075

A flaw was found in OpenSSL. The QUIC protocol implementation retains metadata for ACK-only packets for the lifetime of a connection, leading to excessive memory consumption. This allows a peer to repeatedly send ack-eliciting packets while not acknowledging ACK-only responses to cause memory exhaustion, eventually resulting in a denial of service.

7.5 (High)


                
                  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Fixed: 3 products

https://access.redhat.com/errata/RHSA-2026:59635

Open the full advisory

RHSA-2026:59641

Vulnerability from csaf_redhat - Published: 2026-08-25 21:57 - Updated: 2026-09-14 07:59

Summary

Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update

Severity

Moderate

Scope

8 vulnerabilities in this advisory, including CVE-2026-63075.

CVE-2026-63075

7.5 (High)


                
                  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Fixed: 3 products

https://access.redhat.com/errata/RHSA-2026:59641

Open the full advisory

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

CVE-2026-63075 (GCVE-0-2026-63075)

Vulnerability from osv_almalinux

Vulnerability from osv_almalinux

Solutions

Tags

Sightings

Nomenclature

Related by attack behaviour