Vulnerability-Lookup

alsa-2026:25057

Vulnerability from osv_almalinux

Published

2026-06-10 00:00

Modified

2026-06-11 08:49

Summary

Important: mod_http2 security update

Details

The mod_h2 Apache httpd module implements the HTTP2 protocol (h2+h2c) on top of libnghttp2 for httpd 2.4 servers.

Security Fix(es):

httpd: HTTP/2: Remote Denial of Service via compression bomb and Slowloris-style attack (CVE-2026-49975)

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-2026:25057	ADVISORY
	https://access.redhat.com/security/cve/CVE-2026-49975	REPORT
	https://bugzilla.redhat.com/2485371	REPORT
	https://errata.almalinux.org/9/ALSA-2026-25057.html	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "AlmaLinux:9",
        "name": "mod_http2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.0.26-6.el9_8.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "The mod_h2 Apache httpd module implements the HTTP2 protocol (h2+h2c) on top of libnghttp2 for httpd 2.4 servers.  \n\nSecurity Fix(es):  \n\n  * httpd: HTTP/2: Remote Denial of Service via compression bomb and Slowloris-style attack (CVE-2026-49975)\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-2026:25057",
  "modified": "2026-06-11T08:49:10Z",
  "published": "2026-06-10T00:00:00Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://access.redhat.com/errata/RHSA-2026:25057"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-49975"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/2485371"
    },
    {
      "type": "ADVISORY",
      "url": "https://errata.almalinux.org/9/ALSA-2026-25057.html"
    }
  ],
  "related": [
    "CVE-2026-49975"
  ],
  "summary": "Important: mod_http2 security update"
}

CVE-2026-49975 (GCVE-0-2026-49975)

Vulnerability from cvelistv5 – Published: 2026-06-08 15:26 – Updated: 2026-06-09 15:25

Title

Apache HTTP Server: mod_http2 denial of service

Summary

Memory Allocation with Excessive Size Value vulnerability in Apache HTTP Server's mod_http leads to denial of service via malicious HTTP requests. This issue affects Apache HTTP Server: from 2.4.17 through 2.4.67.

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 (v2.0.3)

CWE

CWE-789 - Memory Allocation with Excessive Size Value

Assigner

apache

References

4 references

URL	Tags
https://httpd.apache.org/security/vulnerabilities…	vendor-advisory
http://www.openwall.com/lists/oss-security/2026/06/03/3
https://lists.debian.org/debian-lts-announce/2026…
http://www.openwall.com/lists/oss-security/2026/0…

Impacted products

1 product

Vendor	Product	Version
Apache Software Foundation	Apache HTTP Server	Affected: 2.4.17 , ≤ 2.4.67 (semver)

Credits

Quang Luong of Calif.IO in collaboration with OpenAI Codex

Show details on NVD website

JSON

To clipboard

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          },
          {
            "url": "https://lists.debian.org/debian-lts-announce/2026/06/msg00009.html"
          },
          {
            "url": "http://www.openwall.com/lists/oss-security/2026/06/08/16"
          }
        ],
        "title": "CVE Program Container"
      },
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        "metrics": [
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              "confidentialityImpact": "NONE",
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              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
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                  },
                  {
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                  },
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                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-09T15:25:51.036143Z",
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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.

Action not permitted

alsa-2026:25057

Vulnerability from osv_almalinux

CVE-2026-49975 (GCVE-0-2026-49975)

Tags

Sightings

Nomenclature