CVE-2026-92899 Apache WSS4J: UsernameToken replay protection bypassed by re-encoding the Nonce
Attackers can bypass replay protection in Apache WSS4J by re-encoding the Nonce, allowing reuse of captured authentication tokens.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-92899?
CVE-2026-92899 is a medium-severity vulnerability in Apache WSS4J, published on 30 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Apache WSS4J remembers the Nonce of each UsernameToken it accepts, so a captured token cannot be reused. It stored the Nonce as raw base64 text, but authentication decodes that text and uses the bytes.The same bytes can be written as base64 in several ways. An attacker who captured an authenticated request could re-send it with a space added to the Nonce: the password digest still verified, but the token no longer matched the remembered one, so the replay was accepted. Since a UsernameToken does not cover the message body, the captured token could then be reused on requests of the attacker's choosing until it expired. Affects deployments with a nonce replay cache configured, as Apache CXF has by default, and only tokens using a password digest. The cache is now keyed on the decoded Nonce. Users are recommended to upgrade to versions 4.0.2 or 3.0.6 or 2.4.4, which fix this issue.
Weakness: CWE-290
Which versions are affected by CVE-2026-92899?
It affects 1 product.
Products include Apache Wss4j.
How do I fix CVE-2026-92899?
No fix has been published for CVE-2026-92899 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-92899 being exploited?
There is no known exploitation of CVE-2026-92899 in the wild and no public exploit code.
Other vulnerabilities in Apache WSS4J
- CVE-2026-88920 Apache WSS4J: SAML Sender-Vouches Authentication Bypass
- CVE-2026-87830 Apache WSS4J: Streaming WS-SecurityPolicy validation may skip element-protection checks.
- CVE-2026-89238 Apache WSS4J: WSS4J EncryptedHeader child confusion causing wrong protected-header selection
- CVE-2026-85532 Apache WSS4J: Insufficient Validation of Derived-Key Parameters
- CVE-2026-92121 Apache WSS4J: WS-SecurityPolicy signature checks skipped in the streaming code after an STR-Transform reference
Sources
Also known as DEBIAN-CVE-2026-92899, GHSA-pw3c-6w58-28w4, UBUNTU-CVE-2026-92899.