Client accepts unsolicited RawPublicKey server certificate type

published 2026-09-27 42 d ago modified 2026-09-29 40 d ago also EUVD-2026-87911

cvss: 8.3; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 32%
public exploits: 0; none known

When using RPK (Raw Public Key), the client side of a TLS 1.2, 1.3 and DTLS 1.2 connection could accept an unsolicited server_cert_type=RawPublicKey which allowed a malicious or misbehaving server to bypass authentication. RPK is off by default and only enabled in --enable-rpk OR --enable-all OR --enable-distro AKA HAVE_RPK builds.

Patch / fix

distros 1 links 1

wolfssl Alpine 3.24 5.9.4-r0

alpine advisories ALPINE-CVE-2026-89136

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

github.com/wolfSSL/wolfssl#11009 pull request

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 40 d ago (2026-09-29)

Exploit prediction

0.38% chance of exploitation in the next 30 days, higher than 32% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	8.3	CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N
CNA	4.0	8.3	CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

wolfSSL wolfSSL

Classification

Weakness

CWE-287 Improper Authentication

References

github.com /wolfSSL/wolfssl/pull/11009

Sources

CVE List CVE-2026-89136
NVD CVE-2026-89136

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary