Vulnerability · Published Jun 25, 2026 · Assigned by wolfSSL
CVE-2026-55961wolfSSL_PKCS7_verify() reports success for degenerate (certs-only) PKCS#7 with no signer
High 8.2
In plain English
A high-severity security flaw in wolfSSL from wolfSSL. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 4% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
wolfSSL_PKCS7_verify() returning success for a degenerate (certs-only) PKCS#7 object that contains no signer. Such an object has empty signerInfos, so the underlying signed-data verification succeeds without authenticating any content. The compatibility-layer verify path now rejects the object when no signer signature has actually been verified, so a PKCS#7 carrying no valid signature is no longer reported as verified. This is enforced regardless of the PKCS7_NOVERIFY flag, which only suppresses signer certificate chain validation and was never intended to waive the requirement that a signature exist. Only affects OpenSSL compatibility builds that call the PKCS7_verify() compatibility API on potentially degenerate PKCS#7 bundles.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.24 | wolfssl | 5.9.2-r0 | ALPINE-CVE-2026-55961 |
| Debian:12 | wolfssl | 5.5.4-2+deb12u3 | DEBIAN-CVE-2026-55961 |
| Debian:13 | wolfssl | 5.7.2-0.1+deb13u2 | DEBIAN-CVE-2026-55961 |
| Ubuntu:22.04:LTS | wolfssl | no fix listed | UBUNTU-CVE-2026-55961 |
| Ubuntu:24.04:LTS | wolfssl | no fix listed | UBUNTU-CVE-2026-55961 |
| Ubuntu:25.10 | wolfssl | no fix listed | UBUNTU-CVE-2026-55961 |
| Ubuntu:26.04:LTS | wolfssl | no fix listed | UBUNTU-CVE-2026-55961 |
| Ubuntu:26.10 | wolfssl | no fix listed | UBUNTU-CVE-2026-55961 |
Affected products (as reported)
Weakness: CWE-347 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N