8.2

CVE-2026-55961: wolfSSL_PKCS7_verify() reports success for degenerate (certs-only) PKCS#7 with no signer

Analyzed
AliasesUBUNTU-CVE-2026-55961DEBIAN-CVE-2026-55961ALPINE-CVE-2026-55961
Published 25-06-2026Last modified 25-06-2026

Vulnerability summary

CVE-2026-55961 is a high (CVSS 8.2) vulnerability in wolfssl. EPSS estimates a 0.15% chance of exploitation in the next 30 days, higher than 3.8% of scored vulnerabilities.

Priority
Prioritisesevere

Severe, CVSS 8.2 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 0% (FIRST, 03-11-2026)

Source freshness unavailable

How is this decided?
CVSS score
8.2/10
010
High · v4.0 (CVE.org)
EPSS score
0.15%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Timeline

  1. 25-06-2026
    PublishedVulnerability first disclosed.
  2. 25-06-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

7 scores · 5 sources · 2 versions

EPSS trend

Probability

0.15%

Chance of exploitation in the next 30 days

Percentile

4%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.15% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Alpine1 product
  • wolfssl≥ 3.15.7, < 5.9.2-r0
Debian1 product
  • wolfssl< 5.5.4-2+deb12u3 | < 5.7.2-0.1+deb13u2
Ubuntu1 product
  • wolfsslAll versions (No fix recorded)
Wolfssl1 product
  • wolfssl≥ 3.15.7, ≤ 5.9.1 | ≥ 3.15.7, < 5.9.2

4 vendors · 4 products

References

6 links