5.3

CVE-2026-6450: CRL critical extension bypass in ParseCRL_Extensions

Analyzed
AliasesUBUNTU-CVE-2026-6450DEBIAN-CVE-2026-6450ALPINE-CVE-2026-6450
Published 25-06-2026Last modified 26-06-2026

Vulnerability summary

CVE-2026-6450 is a medium (CVSS 5.3) Improper Certificate Validation vulnerability in wolfssl. EPSS estimates a 0.33% chance of exploitation in the next 30 days, higher than 26.2% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 1, adjacent network); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
5.3/10
010
Medium · v3.1 (NVD)
EPSS score
0.33%
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. 26-06-2026
    Last modifiedVulnerability information updated.

Description

A CRL critical extension bypass exists in ParseCRL_Extensions where critical extensions are not properly enforced, allowing a crafted CRL with an unhandled critical extension to be accepted. This only affects builds with CRL support enabled and where a crafted CRL had a trusted signature when parsed.

CVSS metrics

7 scores · 5 sources · 2 versions

EPSS trend

Probability

0.33%

Chance of exploitation in the next 30 days

Percentile

26%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.33% 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: adjacent network, administrative account, user interaction (CVSS vector). Other conditions: not stated in public data.

Alpine1 product
  • wolfssl≥ 4.3.0, < 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≥ 4.3.0, ≤ 5.9.1 | ≥ 4.3.0, < 5.9.2

4 vendors · 4 products

References

6 links