CVE-2026-22796 | ASN1_TYPE Type Confusion in the PKCS7_digest_from_attributes() function

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.

Published: 2026-01-27 Last update: 2026-05-12 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-22796 is rated Moderate Risk (45/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.52%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-22796

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-29 0.23% 0.52% +0.29%
2 2026-05-13 0.07% 0.23% +0.16%
3 2026-01-28 0.07%

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-22796

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
3.9 1.4 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-22796

GitHub Security Advisory for CVE-2026-22796

GHSA-r9hf-rxjm-gv2f · Severity: medium — Issue summary: A type confusion vulnerability exists in the signature verification of signed PKCS...

OS Trackers for CVE-2026-22796

vendor priority summary link
alpine CVE-2026-22796: 1 source package rows (openssl); 147 state rows across 6 repos (3.19-main, 3.20-main, 3.21-main, 3.22-main, 3.23-main, edge-main); fixed 5, open 142. https://security.alpinelinux.org/vuln/CVE-2026-22796
debian not yet assigned CVE-2026-22796 not yet assigned priority: Debian including 1 source packages (openssl), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2026-22796
redhat low https://access.redhat.com/security/cve/CVE-2026-22796
suse medium CVE-2026-22796 severity moderate: SUSE including 450 source package names (1.1.1-1.15:libopenssl3-3.2.3-150700.5.24.1, 1.1.1-1.15:openssl-3-3.2.3-150700.5.24.1, …), 1465 product×package rows across 299 product lines (Container private-registry/harbor-core, Container private-registry/harbor-exporter, … (299 product lines)): Fixed 1162, Known Affected 231, Known Not Affected 65, First Fixed 7. https://www.suse.com/security/cve/CVE-2026-22796/
ubuntu low CVE-2026-22796 low priority: Ubuntu including 4 source packages (edk2, nodejs, openssl, openssl1.0), 32 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): needs-triage 11, released 9, not-affected 5, DNE 4, ignored 2, needed 1. https://ubuntu.com/security/CVE-2026-22796

Affected software / configurations for CVE-2026-22796

Vendor Product Version Raw CPE
openssl openssl >= 1.0.2, < 1.0.2zn cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
openssl openssl >= 1.1.1, < 1.1.1ze cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
openssl openssl >= 3.0.0, < 3.0.19 cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
openssl openssl >= 3.3.0, < 3.3.6 cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
openssl openssl >= 3.4.0, < 3.4.4 cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
openssl openssl >= 3.5.0, < 3.5.5 cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*
openssl openssl >= 3.6.0, < 3.6.1 cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*

References for CVE-2026-22796

cvelogic Threat Intelligence