9.8

CVE-2026-88920: apache software foundation apache wss4j Improper Authentication

CVSS: 9.8v3.1CriticalAnalyzed
AliasesUBUNTU-CVE-2026-88920DEBIAN-CVE-2026-88920
Published 30-09-2026Last modified 30-09-2026
Open JSON

Vulnerability summary

CVE-2026-88920 is a critical (CVSS 9.8) Improper Authentication vulnerability in apache software foundation apache wss4j. EPSS estimates a 0.57% chance of exploitation in the next 30 days, higher than 46% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.57%
0%100%
Low · Change unavailable
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 30-09-2026
    PublishedVulnerability first disclosed.
  2. 30-09-2026
    Last modifiedVulnerability information updated.

Description

An authentication bypass in the DOM security processor in Apache WSS4J allows unauthenticated remote attackers to forge authenticated SOAP messages via a crafted unsigned SAML sender-vouches assertion containing an attacker-controlled key. Users are recommended to upgrade to versions 4.0.2 or 3.0.6 or 2.4.4, which fix this issue.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.57%

Chance of exploitation in the next 30 days

Percentile

46%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

01-10-202618-10-2026
EPSS score
0.57%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Apache1 product
  • wss4j< 2.4.4 | ≥ 3.0.0, < 3.0.6 | ≥ 4.0.0, < 4.0.2
Apache software foundation1 product
  • apache wss4j≥ 4.0.0, < 4.0.2 | ≥ 3.0.0, < 3.0.6 | < 2.4.4
Debian1 product
  • wss4jAll versions (No fix recorded)
Ubuntu1 product
  • wss4jAll versions (No fix recorded)

4 vendors · 4 products

References

5 links