CVE-2026-87830 Apache WSS4J: Streaming WS-SecurityPolicy validation may skip element-protection checks.
Remote attackers can bypass WS-SecurityPolicy signature and encryption checks on SOAP elements due to flawed XPath validation in Apache WSS4J.
- 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-2026-87830?
CVE-2026-87830 is a critical 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
In the StAX streaming WS-SecurityPolicy validator, certain relative or unsupported XPath expressions can be converted into paths that never match the actual XML element path. A remote SOAP peer may therefore send a required element without the expected signature or encryption. Users are recommended to upgrade to versions 4.0.2 or 3.0.6 or 2.4.4, which fix this issue.
Weakness: CWE-917
Which versions are affected by CVE-2026-87830?
It affects 1 product.
Products include Apache Wss4j.
How do I fix CVE-2026-87830?
No fix has been published for CVE-2026-87830 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-87830 being exploited?
There is no known exploitation of CVE-2026-87830 in the wild and no public exploit code.
Other vulnerabilities in Apache WSS4J
- CVE-2026-88920 Apache WSS4J: SAML Sender-Vouches Authentication Bypass
- CVE-2026-89238 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
- CVE-2026-95616 Apache WSS4J: Unauthenticated denial of service via integer overflow in DER parsing of X.509 certificate extensions
Sources
Also known as DEBIAN-CVE-2026-87830, GHSA-66vg-36xv-j6x4, UBUNTU-CVE-2026-87830.