Wss4j:
Affects wss4jSource GCVE Database
Not known to be exploited · CVSS 9.1 Critical · fixed in 4.0.2 : patch wss4j as a priority.
Data as of 5 Nov 2026, 00:01 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 12% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 4.0.2
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 30 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 4 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10wss4jpkg:deb/ubuntu/wss4j?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSwss4jpkg:deb/ubuntu/wss4j?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSwss4jpkg:deb/ubuntu/wss4j?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 20.04 LTSwss4jpkg:deb/ubuntu/wss4j?arch=source&distro=focalOther threats | Affected
| Fixed in– |
Ubuntu 16.04 LTSwss4jpkg:deb/ubuntu/wss4j?arch=source&distro=xenialOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Users should upgrade to wss4j versions 4.0.2, 3.0.6, or 2.4.4, which contain fixes for this vulnerability. Applying these official fixes will prevent exploitation of the XPath expression handling flaw in the WS-SecurityPolicy validator.
Description
A vulnerability in the StAX streaming WS-SecurityPolicy validator of wss4j allows certain relative or unsupported XPath expressions to be misinterpreted, causing required SOAP elements to be accepted without the expected signature or encryption. This can enable a remote attacker to bypass security controls. The issue is fixed in wss4j versions 4.0.2, 3.0.6, and 2.4.4.