8.2

CVE-2026-55960: Un-negotiated Raw Public Key (RFC 7250) accepted in place of X.509, bypassing chain validation

Analyzed
AliasesUBUNTU-CVE-2026-55960DEBIAN-CVE-2026-55960ALPINE-CVE-2026-55960
Published 25-06-2026Last modified 26-06-2026

Vulnerability summary

CVE-2026-55960 is a high (CVSS 8.2) Improper Certificate Validation vulnerability in wolfssl. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 14.4% 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
0.23%
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

Un-negotiated Raw Public Key (RFC 7250) accepted in place of an X.509 certificate, bypassing chain validation. A raw public key has no chain, so ParseCertRelative() accepts it without performing any trust verification; it must therefore only be accepted when RPK was actually negotiated for that peer. The check now defaults the expected type to X.509 (per RFC 7250/8446) when no type was negotiated, comparing against the received server certificate type on the client and the selected client certificate type on the server, and rejects any mismatch, including an un-negotiated raw public key, with UNSUPPORTED_CERTIFICATE. Only affects builds with Raw Public Key support (HAVE_RPK) enabled - disabled by default in a standalone build, but included in --enable-all.

CVSS metrics

7 scores · 5 sources · 2 versions

EPSS trend

Probability

0.23%

Chance of exploitation in the next 30 days

Percentile

14%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.23% 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≥ 5.6.4, < 5.9.2-r0
Debian1 product
  • wolfsslAll versions (No fix recorded) | < 5.7.2-0.1+deb13u2
Ubuntu1 product
  • wolfsslAll versions (No fix recorded)
Wolfssl1 product
  • wolfssl≥ 5.6.4, ≤ 5.9.1 | ≥ 5.6.4, < 5.9.2

4 vendors · 4 products

References

6 links