Vulnerability · Published Sep 18, 2026 · Assigned by redhat

CVE-2026-93578Io.netty/netty-handler-ssl-ocsp: netty: missing extended key usage (eku) check in ocsp client allows certificate revocation bypass

Medium 5.9

In plain English

A medium-severity security flaw in Red Hat build of Apache Camel for Spring Boot 4 from Red Hat. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 13% of all known vulnerabilities).

Severity (CVSS 3.1)5.9Medium

Exploit odds (30 days)0.2%top 86.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

A flaw was found in Netty's Online Certificate Status Protocol (OCSP) Client. The client fails to verify the 'id-kp-OCSPSigning' Extended Key Usage (EKU) in OCSP responder certificates. A remote attacker, holding any valid certificate issued by the same Certificate Authority (CA), can exploit this by forging 'GOOD' OCSP responses for revoked certificates. This bypasses certificate revocation checks, allowing applications using Netty's OCSP Client to accept certificates that should have been revoked, leading to an authorization bypass.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	netty	no fix listed	DEBIAN-CVE-2026-93578
Debian:13	netty	no fix listed	DEBIAN-CVE-2026-93578
Debian:14	netty	no fix listed	DEBIAN-CVE-2026-93578
Ubuntu:26.10	netty	no fix listed	UBUNTU-CVE-2026-93578

Affected products (as reported)

Vendor	Product	Versions
Red Hat	Red Hat build of Apache Camel for Spring Boot 4	see references

Weakness: CWE-1035 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

References

https://access.redhat.com/security/cve/CVE-2026-93578 vdb-entry, x_refsource_REDHAT
RHBZ#2536969 issue-tracking, x_refsource_REDHAT