CVE-2026-55961
PKCS7_verify() may return success for degenerate PKCS#7 with no signer, bypassing signature check.
Is CVE-2026-55961 being exploited?
Not confirmed. CVE-2026-55961 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.15% probability of exploitation in the next 30 days.
How severe is CVE-2026-55961?
CVE-2026-55961 is rated High with a CVSS score of 8.2. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-55961?
Yes. A fix has been recorded for CVE-2026-55961. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-55961 affect?
CVE-2026-55961 affects wolfSSL/OpenSSL compatibility builds using PKCS7_verify(). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-55961?
Upgrade to patched release when available; review PKCS7_verify usage.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote code execution via degenerate PKCS#7 data accepted as verified without a signer.
Patch when possible
- affected>= 3.15.7 and <= 5.9.1
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.