Vulnerability-Lookup

GHSA-R9HF-RXJM-GV2F

Vulnerability from github – Published: 2026-01-27 18:32 – Updated: 2026-01-27 18:32

Details

Impact summary: An application performing signature verification of PKCS#7 data or calling directly the PKCS7_digest_from_attributes() function can be caused to dereference an invalid or NULL pointer when reading, resulting in a Denial of Service.

The function PKCS7_digest_from_attributes() accesses the message digest attribute value without validating its type. When the type is not V_ASN1_OCTET_STRING, this results in accessing invalid memory through the ASN1_TYPE union, causing a crash.

Exploiting this vulnerability requires an attacker to provide a malformed signed PKCS#7 to an application that verifies it. The impact of the exploit is just a Denial of Service, the PKCS7 API is legacy and applications should be using the CMS API instead. For these reasons the issue was assessed as Low severity.

The FIPS modules in 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the PKCS#7 parsing implementation is outside the OpenSSL FIPS module boundary.

OpenSSL 3.6, 3.5, 3.4, 3.3, 3.0, 1.1.1 and 1.0.2 are vulnerable to this issue.

Severity ?

5.3 (Medium)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-22796"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-754"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-01-27T16:16:35Z",
    "severity": "MODERATE"
  },
  "details": "Issue summary: A type confusion vulnerability exists in the signature\nverification of signed PKCS#7 data where an ASN1_TYPE union member is\naccessed without first validating the type, causing an invalid or NULL\npointer dereference when processing malformed PKCS#7 data.\n\nImpact summary: An application performing signature verification of PKCS#7\ndata or calling directly the PKCS7_digest_from_attributes() function can be\ncaused to dereference an invalid or NULL pointer when reading, resulting in\na Denial of Service.\n\nThe function PKCS7_digest_from_attributes() accesses the message digest attribute\nvalue without validating its type. When the type is not V_ASN1_OCTET_STRING,\nthis results in accessing invalid memory through the ASN1_TYPE union, causing\na crash.\n\nExploiting this vulnerability requires an attacker to provide a malformed\nsigned PKCS#7 to an application that verifies it. The impact of the\nexploit is just a Denial of Service, the PKCS7 API is legacy and applications\nshould be using the CMS API instead. For these reasons the issue was\nassessed as Low severity.\n\nThe FIPS modules in 3.5, 3.4, 3.3 and 3.0 are not affected by this issue,\nas the PKCS#7 parsing implementation is outside the OpenSSL FIPS module\nboundary.\n\nOpenSSL 3.6, 3.5, 3.4, 3.3, 3.0, 1.1.1 and 1.0.2 are vulnerable to this issue.",
  "id": "GHSA-r9hf-rxjm-gv2f",
  "modified": "2026-01-27T18:32:16Z",
  "published": "2026-01-27T18:32:16Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-22796"
    },
    {
      "type": "WEB",
      "url": "https://github.com/openssl/openssl/commit/2502e7b7d4c0cf4f972a881641fe09edc67aeec4"
    },
    {
      "type": "WEB",
      "url": "https://github.com/openssl/openssl/commit/572844beca95068394c916626a6d3a490f831a49"
    },
    {
      "type": "WEB",
      "url": "https://github.com/openssl/openssl/commit/7bbca05be55b129651d9df4bdb92becc45002c12"
    },
    {
      "type": "WEB",
      "url": "https://github.com/openssl/openssl/commit/eeee3cbd4d682095ed431052f00403004596373e"
    },
    {
      "type": "WEB",
      "url": "https://github.com/openssl/openssl/commit/ef2fb66ec571564d64d1c74a12e388a2a54d05d2"
    },
    {
      "type": "WEB",
      "url": "https://openssl-library.org/news/secadv/20260127.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:L",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-22796 (GCVE-0-2026-22796)

Vulnerability from cvelistv5 – Published: 2026-01-27 16:01 – Updated: 2026-01-27 16:28

Title

ASN1_TYPE Type Confusion in the PKCS7_digest_from_attributes() function

Summary

Issue summary: A type confusion vulnerability exists in the signature verification of signed PKCS#7 data where an ASN1_TYPE union member is accessed without first validating the type, causing an invalid or NULL pointer dereference when processing malformed PKCS#7 data. Impact summary: An application performing signature verification of PKCS#7 data or calling directly the PKCS7_digest_from_attributes() function can be caused to dereference an invalid or NULL pointer when reading, resulting in a Denial of Service. The function PKCS7_digest_from_attributes() accesses the message digest attribute value without validating its type. When the type is not V_ASN1_OCTET_STRING, this results in accessing invalid memory through the ASN1_TYPE union, causing a crash. Exploiting this vulnerability requires an attacker to provide a malformed signed PKCS#7 to an application that verifies it. The impact of the exploit is just a Denial of Service, the PKCS7 API is legacy and applications should be using the CMS API instead. For these reasons the issue was assessed as Low severity. The FIPS modules in 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the PKCS#7 parsing implementation is outside the OpenSSL FIPS module boundary. OpenSSL 3.6, 3.5, 3.4, 3.3, 3.0, 1.1.1 and 1.0.2 are vulnerable to this issue.

Severity ?

No CVSS data available.

CWE

CWE-754 - Improper Check for Unusual or Exceptional Conditions

Assigner

openssl

References

URL

Tags

	https://openssl-library.org/news/secadv/20260127.txt	vendor-advisory
	https://github.com/openssl/openssl/commit/ef2fb66…	patch
	https://github.com/openssl/openssl/commit/2502e7b…	patch
	https://github.com/openssl/openssl/commit/7bbca05…	patch
	https://github.com/openssl/openssl/commit/eeee3cb…	patch
	https://github.com/openssl/openssl/commit/572844b…	patch

Impacted products

	Vendor	Product	Version
	OpenSSL	OpenSSL	Affected: 3.6.0 , < 3.6.1 (semver) Affected: 3.5.0 , < 3.5.5 (semver) Affected: 3.4.0 , < 3.4.4 (semver) Affected: 3.3.0 , < 3.3.6 (semver) Affected: 3.0.0 , < 3.0.19 (semver) Affected: 1.1.1 , < 1.1.1ze (custom) Affected: 1.0.2 , < 1.0.2zn (custom)

Credits

Luigino Camastra (Aisle Research) Bob Beck

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "LOW",
              "baseScore": 5.3,
              "baseSeverity": "MEDIUM",
              "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:L",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-22796",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-01-27T16:27:50.351586Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-01-27T16:28:52.046Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "OpenSSL",
          "vendor": "OpenSSL",
          "versions": [
            {
              "lessThan": "3.6.1",
              "status": "affected",
              "version": "3.6.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.5.5",
              "status": "affected",
              "version": "3.5.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.4.4",
              "status": "affected",
              "version": "3.4.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.3.6",
              "status": "affected",
              "version": "3.3.0",
              "versionType": "semver"
            },
            {
              "lessThan": "3.0.19",
              "status": "affected",
              "version": "3.0.0",
              "versionType": "semver"
            },
            {
              "lessThan": "1.1.1ze",
              "status": "affected",
              "version": "1.1.1",
              "versionType": "custom"
            },
            {
              "lessThan": "1.0.2zn",
              "status": "affected",
              "version": "1.0.2",
              "versionType": "custom"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "reporter",
          "value": "Luigino Camastra (Aisle Research)"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "Bob Beck"
        }
      ],
      "datePublic": "2026-01-27T14:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "Issue summary: A type confusion vulnerability exists in the signature\u003cbr\u003everification of signed PKCS#7 data where an ASN1_TYPE union member is\u003cbr\u003eaccessed without first validating the type, causing an invalid or NULL\u003cbr\u003epointer dereference when processing malformed PKCS#7 data.\u003cbr\u003e\u003cbr\u003eImpact summary: An application performing signature verification of PKCS#7\u003cbr\u003edata or calling directly the PKCS7_digest_from_attributes() function can be\u003cbr\u003ecaused to dereference an invalid or NULL pointer when reading, resulting in\u003cbr\u003ea Denial of Service.\u003cbr\u003e\u003cbr\u003eThe function PKCS7_digest_from_attributes() accesses the message digest attribute\u003cbr\u003evalue without validating its type. When the type is not V_ASN1_OCTET_STRING,\u003cbr\u003ethis results in accessing invalid memory through the ASN1_TYPE union, causing\u003cbr\u003ea crash.\u003cbr\u003e\u003cbr\u003eExploiting this vulnerability requires an attacker to provide a malformed\u003cbr\u003esigned PKCS#7 to an application that verifies it. The impact of the\u003cbr\u003eexploit is just a Denial of Service, the PKCS7 API is legacy and applications\u003cbr\u003eshould be using the CMS API instead. For these reasons the issue was\u003cbr\u003eassessed as Low severity.\u003cbr\u003e\u003cbr\u003eThe FIPS modules in 3.5, 3.4, 3.3 and 3.0 are not affected by this issue,\u003cbr\u003eas the PKCS#7 parsing implementation is outside the OpenSSL FIPS module\u003cbr\u003eboundary.\u003cbr\u003e\u003cbr\u003eOpenSSL 3.6, 3.5, 3.4, 3.3, 3.0, 1.1.1 and 1.0.2 are vulnerable to this issue."
            }
          ],
          "value": "Issue summary: A type confusion vulnerability exists in the signature\nverification of signed PKCS#7 data where an ASN1_TYPE union member is\naccessed without first validating the type, causing an invalid or NULL\npointer dereference when processing malformed PKCS#7 data.\n\nImpact summary: An application performing signature verification of PKCS#7\ndata or calling directly the PKCS7_digest_from_attributes() function can be\ncaused to dereference an invalid or NULL pointer when reading, resulting in\na Denial of Service.\n\nThe function PKCS7_digest_from_attributes() accesses the message digest attribute\nvalue without validating its type. When the type is not V_ASN1_OCTET_STRING,\nthis results in accessing invalid memory through the ASN1_TYPE union, causing\na crash.\n\nExploiting this vulnerability requires an attacker to provide a malformed\nsigned PKCS#7 to an application that verifies it. The impact of the\nexploit is just a Denial of Service, the PKCS7 API is legacy and applications\nshould be using the CMS API instead. For these reasons the issue was\nassessed as Low severity.\n\nThe FIPS modules in 3.5, 3.4, 3.3 and 3.0 are not affected by this issue,\nas the PKCS#7 parsing implementation is outside the OpenSSL FIPS module\nboundary.\n\nOpenSSL 3.6, 3.5, 3.4, 3.3, 3.0, 1.1.1 and 1.0.2 are vulnerable to this issue."
        }
      ],
      "metrics": [
        {
          "format": "other",
          "other": {
            "content": {
              "text": "Low"
            },
            "type": "https://openssl-library.org/policies/general/security-policy/"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-754",
              "description": "CWE-754 Improper Check for Unusual or Exceptional Conditions",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-01-27T16:01:28.150Z",
        "orgId": "3a12439a-ef3a-4c79-92e6-6081a721f1e5",
        "shortName": "openssl"
      },
      "references": [
        {
          "name": "OpenSSL Advisory",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://openssl-library.org/news/secadv/20260127.txt"
        },
        {
          "name": "3.6.1 git commit",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/openssl/openssl/commit/ef2fb66ec571564d64d1c74a12e388a2a54d05d2"
        },
        {
          "name": "3.5.5 git commit",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/openssl/openssl/commit/2502e7b7d4c0cf4f972a881641fe09edc67aeec4"
        },
        {
          "name": "3.4.4 git commit",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/openssl/openssl/commit/7bbca05be55b129651d9df4bdb92becc45002c12"
        },
        {
          "name": "3.3.6 git commit",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/openssl/openssl/commit/eeee3cbd4d682095ed431052f00403004596373e"
        },
        {
          "name": "3.0.19 git commit",
          "tags": [
            "patch"
          ],
          "url": "https://github.com/openssl/openssl/commit/572844beca95068394c916626a6d3a490f831a49"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "ASN1_TYPE Type Confusion in the PKCS7_digest_from_attributes() function",
      "x_generator": {
        "engine": "Vulnogram 0.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "3a12439a-ef3a-4c79-92e6-6081a721f1e5",
    "assignerShortName": "openssl",
    "cveId": "CVE-2026-22796",
    "datePublished": "2026-01-27T16:01:28.150Z",
    "dateReserved": "2026-01-09T18:54:13.571Z",
    "dateUpdated": "2026-01-27T16:28:52.046Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date

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

GHSA-R9HF-RXJM-GV2F

CVE-2026-22796 (GCVE-0-2026-22796)

Tags

Sightings

Nomenclature