CVE-2026-22796

MEDIUM EPSS 39.1%
Published Jan 27, 20265mo ago · Modified Jun 17, 20261w ago
5.3 CVSS 3.1
Medium
Find Similar
Published Jan 27, 2026 5mo ago
Last Modified Jun 17, 2026 1w ago

Description

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.

CVSS Details

Base Score
5.3
Exploitability
3.9
Impact
1.4
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability Low

Threat Intelligence

EPSS Exploit Probability
39.1% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-754

Affected Products 7

VendorProductVersionRange
opensslopenssl*≥1.0.2  –  <1.0.2zn
opensslopenssl*≥1.1.1  –  <1.1.1ze
opensslopenssl*≥3.0.0  –  <3.0.19
opensslopenssl*≥3.3.0  –  <3.3.6
opensslopenssl*≥3.4.0  –  <3.4.4
opensslopenssl*≥3.5.0  –  <3.5.5
opensslopenssl*≥3.6.0  –  <3.6.1

References 7

  • cert-portal.siemens.com https://cert-portal.siemens.com/productcert/html/ssa-265688.html
  • github.com https://github.com/openssl/openssl/commit/2502e7b7d4c0cf4f972a881641fe09edc67aeec4
    Patch
  • github.com https://github.com/openssl/openssl/commit/572844beca95068394c916626a6d3a490f831a49
    Patch
  • github.com https://github.com/openssl/openssl/commit/7bbca05be55b129651d9df4bdb92becc45002c12
    Patch
  • github.com https://github.com/openssl/openssl/commit/eeee3cbd4d682095ed431052f00403004596373e
    Patch
  • github.com https://github.com/openssl/openssl/commit/ef2fb66ec571564d64d1c74a12e388a2a54d05d2
    Patch
  • openssl-library.org https://openssl-library.org/news/secadv/20260127.txt
    Vendor Advisory

Remediation

  • github.com https://github.com/openssl/openssl/commit/2502e7b7d4c0cf4f972a881641fe09edc67aeec4
    Patch
  • github.com https://github.com/openssl/openssl/commit/572844beca95068394c916626a6d3a490f831a49
    Patch
  • github.com https://github.com/openssl/openssl/commit/7bbca05be55b129651d9df4bdb92becc45002c12
    Patch
  • github.com https://github.com/openssl/openssl/commit/eeee3cbd4d682095ed431052f00403004596373e
    Patch
  • github.com https://github.com/openssl/openssl/commit/ef2fb66ec571564d64d1c74a12e388a2a54d05d2
    Patch