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OESA-2026-2042 (CVE-2026-28387)

Vulnerability from osv_openeuler – Published: 2026-04-25 11:11 – Updated: 2026-08-06 11:11 – Source website
VLAI
Summary
openssl security update
Details

Security Fix(es):

Issue summary: An uncommon configuration of clients performing DANE TLSA-based server authentication, when paired with uncommon server DANE TLSA records, may result in a use-after-free and/or double-free on the client side.

Impact summary: A use after free can have a range of potential consequences such as the corruption of valid data, crashes or execution of arbitrary code.

However, the issue only affects clients that make use of TLSA records with both the PKIX-TA(0/PKIX-EE(1) certificate usages and the DANE-TA(2) certificate usage.

By far the most common deployment of DANE is in SMTP MTAs for which RFC7672 recommends that clients treat as 'unusable' any TLSA records that have the PKIX certificate usages. These SMTP (or other similar) clients are not vulnerable to this issue. Conversely, any clients that support only the PKIX usages, and ignore the DANE-TA(2) usage are also not vulnerable.

The client would also need to be communicating with a server that publishes a TLSA RRset with both types of TLSA records.

No FIPS modules are affected by this issue, the problem code is outside the FIPS module boundary.(CVE-2026-28387)

Issue summary: When a delta CRL that contains a Delta CRL Indicator extension is processed a NULL pointer dereference might happen if the required CRL Number extension is missing.

Impact summary: A NULL pointer dereference can trigger a crash which leads to a Denial of Service for an application.

When CRL processing and delta CRL processing is enabled during X.509 certificate verification, the delta CRL processing does not check whether the CRL Number extension is NULL before dereferencing it. When a malformed delta CRL file is being processed, this parameter can be NULL, causing a NULL pointer dereference.

Exploiting this issue requires the X509_V_FLAG_USE_DELTAS flag to be enabled in the verification context, the certificate being verified to contain a freshestCRL extension or the base CRL to have the EXFLAG_FRESHEST flag set, and an attacker to provide a malformed CRL to an application that processes it.

The vulnerability is limited to Denial of Service and cannot be escalated to achieve code execution or memory disclosure. For that reason the issue was assessed as Low severity according to our Security Policy.

The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.(CVE-2026-28388)

Issue summary: During processing of a crafted CMS EnvelopedData message with KeyAgreeRecipientInfo a NULL pointer dereference can happen.

Impact summary: Applications that process attacker-controlled CMS data may crash before authentication or cryptographic operations occur resulting in Denial of Service.

When a CMS EnvelopedData message that uses KeyAgreeRecipientInfo is processed, the optional parameters field of KeyEncryptionAlgorithmIdentifier is examined without checking for its presence. This results in a NULL pointer dereference if the field is missing.

Applications and services that call CMS_decrypt() on untrusted input (e.g., S/MIME processing or CMS-based protocols) are vulnerable.

The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.(CVE-2026-28389)

Issue summary: During processing of a crafted CMS EnvelopedData message with KeyTransportRecipientInfo a NULL pointer dereference can happen.

Impact summary: Applications that process attacker-controlled CMS data may crash before authentication or cryptographic operations occur resulting in Denial of Service.

When a CMS EnvelopedData message that uses KeyTransportRecipientInfo with RSA-OAEP encryption is processed, the optional parameters field of RSA-OAEP SourceFunc algorithm identifier is examined without checking for its presence. This results in a NULL pointer dereference if the field is missing.

Applications and services that call CMS_decrypt() on untrusted input (e.g., S/MIME processing or CMS-based protocols) are vulnerable.

The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.(CVE-2026-28390)

Issue summary: Converting an excessively large OCTET STRING value to a hexadecimal string leads to a heap buffer overflow on 32 bit platforms.

Impact summary: A heap buffer overflow may lead to a crash or possibly an attacker controlled code execution or other undefined behavior.

If an attacker can supply a crafted X.509 certificate with an excessively large OCTET STRING value in extensions such as the Subject Key Identifier (SKID) or Authority Key Identifier (AKID) which are being converted to hex, the size of the buffer needed for the result is calculated as multiplication of the input length by 3. On 32 bit platforms, this multiplication may overflow resulting in the allocation of a smaller buffer and a heap buffer overflow.

Applications and services that print or log contents of untrusted X.509 certificates are vulnerable to this issue. As the certificates would have to have sizes of over 1 Gigabyte, printing or logging such certificates is a fairly unlikely operation and only 32 bit platforms are affected, this issue was assigned Low severity.

The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.(CVE-2026-31789)

Issue summary: Applications using RSASVE key encapsulation to establish a secret encryption key can send contents of an uninitialized memory buffer to a malicious peer.

Impact summary: The uninitialized buffer might contain sensitive data from the previous execution of the application process which leads to sensitive data leakage to an attacker.

RSA_public_encrypt() returns the number of bytes written on success and -1 on error. The affected code tests only whether the return value is non-zero. As a result, if RSA encryption fails, encapsulation can still return success to the caller, set the output lengths, and leave the caller to use the contents of the ciphertext buffer as if a valid KEM ciphertext had been produced.

If applications use EVP_PKEY_encapsulate() with RSA/RSASVE on an attacker-supplied invalid RSA public key without first validating that key, then this may cause stale or uninitialized contents of the caller-provided ciphertext buffer to be disclosed to the attacker in place of the KEM ciphertext.

As a workaround calling EVP_PKEY_public_check() or EVP_PKEY_public_check_quick() before EVP_PKEY_encapsulate() will mitigate the issue.

The FIPS modules in 3.6, 3.5, 3.4, 3.3, 3.1 and 3.0 are affected by this issue.(CVE-2026-31790)

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

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "openssl-3.0.12-47.oe2403sp1.aarch64.rpm",
          "openssl-debuginfo-3.0.12-47.oe2403sp1.aarch64.rpm",
          "openssl-debugsource-3.0.12-47.oe2403sp1.aarch64.rpm",
          "openssl-devel-3.0.12-47.oe2403sp1.aarch64.rpm",
          "openssl-libs-3.0.12-47.oe2403sp1.aarch64.rpm",
          "openssl-perl-3.0.12-47.oe2403sp1.aarch64.rpm"
        ],
        "noarch": [
          "openssl-help-3.0.12-47.oe2403sp1.noarch.rpm"
        ],
        "src": [
          "openssl-3.0.12-47.oe2403sp1.src.rpm"
        ],
        "x86_64": [
          "openssl-3.0.12-47.oe2403sp1.x86_64.rpm",
          "openssl-debuginfo-3.0.12-47.oe2403sp1.x86_64.rpm",
          "openssl-debugsource-3.0.12-47.oe2403sp1.x86_64.rpm",
          "openssl-devel-3.0.12-47.oe2403sp1.x86_64.rpm",
          "openssl-libs-3.0.12-47.oe2403sp1.x86_64.rpm",
          "openssl-perl-3.0.12-47.oe2403sp1.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS-SP1",
        "name": "openssl",
        "purl": "pkg:rpm/openEuler/openssl\u0026distro=openEuler-24.03-LTS-SP1"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.0.12-47.oe2403sp1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "High"
  },
  "details": "Security Fix(es):\n\nIssue summary: An uncommon configuration of clients performing DANE TLSA-based\nserver authentication, when paired with uncommon server DANE TLSA records, may\nresult in a use-after-free and/or double-free on the client side.\n\nImpact summary: A use after free can have a range of potential consequences\nsuch as the corruption of valid data, crashes or execution of arbitrary code.\n\nHowever, the issue only affects clients that make use of TLSA records with both\nthe PKIX-TA(0/PKIX-EE(1) certificate usages and the DANE-TA(2) certificate\nusage.\n\nBy far the most common deployment of DANE is in SMTP MTAs for which RFC7672\nrecommends that clients treat as \u0026apos;unusable\u0026apos; any TLSA records that have the PKIX\ncertificate usages.  These SMTP (or other similar) clients are not vulnerable\nto this issue.  Conversely, any clients that support only the PKIX usages, and\nignore the DANE-TA(2) usage are also not vulnerable.\n\nThe client would also need to be communicating with a server that publishes a\nTLSA RRset with both types of TLSA records.\n\nNo FIPS modules are affected by this issue, the problem code is outside the\nFIPS module boundary.(CVE-2026-28387)\n\nIssue summary: When a delta CRL that contains a Delta CRL Indicator extension\nis processed a NULL pointer dereference might happen if the required CRL\nNumber extension is missing.\n\nImpact summary: A NULL pointer dereference can trigger a crash which\nleads to a Denial of Service for an application.\n\nWhen CRL processing and delta CRL processing is enabled during X.509\ncertificate verification, the delta CRL processing does not check\nwhether the CRL Number extension is NULL before dereferencing it.\nWhen a malformed delta CRL file is being processed, this parameter\ncan be NULL, causing a NULL pointer dereference.\n\nExploiting this issue requires the X509_V_FLAG_USE_DELTAS flag to be enabled in\nthe verification context, the certificate being verified to contain a\nfreshestCRL extension or the base CRL to have the EXFLAG_FRESHEST flag set, and\nan attacker to provide a malformed CRL to an application that processes it.\n\nThe vulnerability is limited to Denial of Service and cannot be escalated to\nachieve code execution or memory disclosure. For that reason the issue was\nassessed as Low severity according to our Security Policy.\n\nThe FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue,\nas the affected code is outside the OpenSSL FIPS module boundary.(CVE-2026-28388)\n\nIssue summary: During processing of a crafted CMS EnvelopedData message\nwith KeyAgreeRecipientInfo a NULL pointer dereference can happen.\n\nImpact summary: Applications that process attacker-controlled CMS data may\ncrash before authentication or cryptographic operations occur resulting in\nDenial of Service.\n\nWhen a CMS EnvelopedData message that uses KeyAgreeRecipientInfo is\nprocessed, the optional parameters field of KeyEncryptionAlgorithmIdentifier\nis examined without checking for its presence. This results in a NULL\npointer dereference if the field is missing.\n\nApplications and services that call CMS_decrypt() on untrusted input\n(e.g., S/MIME processing or CMS-based protocols) are vulnerable.\n\nThe FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this\nissue, as the affected code is outside the OpenSSL FIPS module boundary.(CVE-2026-28389)\n\nIssue summary: During processing of a crafted CMS EnvelopedData message\nwith KeyTransportRecipientInfo a NULL pointer dereference can happen.\n\nImpact summary: Applications that process attacker-controlled CMS data may\ncrash before authentication or cryptographic operations occur resulting in\nDenial of Service.\n\nWhen a CMS EnvelopedData message that uses KeyTransportRecipientInfo with\nRSA-OAEP encryption is processed, the optional parameters field of\nRSA-OAEP SourceFunc algorithm identifier is examined without checking\nfor its presence. This results in a NULL pointer dereference if the field\nis missing.\n\nApplications and services that call CMS_decrypt() on untrusted input\n(e.g., S/MIME processing or CMS-based protocols) are vulnerable.\n\nThe FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this\nissue, as the affected code is outside the OpenSSL FIPS module boundary.(CVE-2026-28390)\n\nIssue summary: Converting an excessively large OCTET STRING value to\na hexadecimal string leads to a heap buffer overflow on 32 bit platforms.\n\nImpact summary: A heap buffer overflow may lead to a crash or possibly\nan attacker controlled code execution or other undefined behavior.\n\nIf an attacker can supply a crafted X.509 certificate with an excessively\nlarge OCTET STRING value in extensions such as the Subject Key Identifier\n(SKID) or Authority Key Identifier (AKID) which are being converted to hex,\nthe size of the buffer needed for the result is calculated as multiplication\nof the input length by 3. On 32 bit platforms, this multiplication may overflow\nresulting in the allocation of a smaller buffer and a heap buffer overflow.\n\nApplications and services that print or log contents of untrusted X.509\ncertificates are vulnerable to this issue. As the certificates would have\nto have sizes of over 1 Gigabyte, printing or logging such certificates\nis a fairly unlikely operation and only 32 bit platforms are affected,\nthis issue was assigned Low severity.\n\nThe FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this\nissue, as the affected code is outside the OpenSSL FIPS module boundary.(CVE-2026-31789)\n\nIssue summary: Applications using RSASVE key encapsulation to establish\na secret encryption key can send contents of an uninitialized memory buffer to\na malicious peer.\n\nImpact summary: The uninitialized buffer might contain sensitive data from the\nprevious execution of the application process which leads to sensitive data\nleakage to an attacker.\n\nRSA_public_encrypt() returns the number of bytes written on success and -1\non error. The affected code tests only whether the return value is non-zero.\nAs a result, if RSA encryption fails, encapsulation can still return success to\nthe caller, set the output lengths, and leave the caller to use the contents of\nthe ciphertext buffer as if a valid KEM ciphertext had been produced.\n\nIf applications use EVP_PKEY_encapsulate() with RSA/RSASVE on an\nattacker-supplied invalid RSA public key without first validating that key,\nthen this may cause stale or uninitialized contents of the caller-provided\nciphertext buffer to be disclosed to the attacker in place of the KEM\nciphertext.\n\nAs a workaround calling EVP_PKEY_public_check() or\nEVP_PKEY_public_check_quick() before EVP_PKEY_encapsulate() will mitigate\nthe issue.\n\nThe FIPS modules in 3.6, 3.5, 3.4, 3.3, 3.1 and 3.0 are affected by this issue.(CVE-2026-31790)",
  "id": "OESA-2026-2042",
  "modified": "2026-08-06T11:11:02Z",
  "published": "2026-04-25T11:11:02Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-2042"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-28387"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-28388"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-28389"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-28390"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31789"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31790"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "openssl security update",
  "upstream": [
    "CVE-2026-28387",
    "CVE-2026-28388",
    "CVE-2026-28389",
    "CVE-2026-28390",
    "CVE-2026-31789",
    "CVE-2026-31790"
  ]
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • 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.


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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.