Security Digest · Vulnerability record
CVE-2026-50627: Apache CXF OAuth2 Missing JWT Audience and Issuer Validation in Access Token Validator
The JwtAccessTokenValidator class in Apache CXF fails to validate the 'aud' (Audience) claims of incoming JWT access tokens.
CVSS 8.1 High EPSS 0.8% · p55
Should you act?
Normal patch cycle
No exploitation signal; fix it in your next routine update if you are affected. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.8%, percentile 55: FIRST’s model estimates a 0.8% chance of exploitation activity in the next 30 days, higher than 55% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Needs an account (low (any account)). Exposure depends on who can log in.
- Only applies if your dependency tree includes
org.apache.cxf:cxf-rt-rs-security-oauth2(Maven) >= 4.2.0, < 4.2.2, fixed in 4.2.2;org.apache.cxf:cxf-rt-rs-security-oauth2(Maven) < 4.1.7, fixed in 4.1.7. Check your lockfile, including transitive dependencies.
What it is
The JwtAccessTokenValidator class in Apache CXF fails to validate the 'aud' (Audience) claims of incoming JWT access tokens. This allows a JWT issued for one Resource Server to be successfully replayed against a completely different Resource Server, leading to Token Confusion/Routing attacks. Users are recommended to upgrade to versions 4.2.2 or 4.1.7 or 3.6.12, which fixes this issue.
From the GitHub advisory
The JwtAccessTokenValidator class in Apache CXF fails to validate the 'aud' (Audience) claims of incoming JWT access tokens. This allows a JWT issued for one Resource Server to be successfully replayed against a completely different Resource Server, leading to Token Confusion/Routing attacks. Users are recommended to upgrade to versions 4.2.2 or 4.1.7, which fixes this issue.
Weakness type: CWE-289, CWE-303.
Product: org.apache.cxf:cxf-rt-rs-security-oauth2 (Maven) · Assigned by: apache · Published: 2026-06-12
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| Maven | org.apache.cxf:cxf-rt-rs-security-oauth2 | >= 4.2.0, < 4.2.2 | 4.2.2 |
| Maven | org.apache.cxf:cxf-rt-rs-security-oauth2 | < 4.1.7 | 4.1.7 |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| Apache Software Foundation | Apache CXF | 4.2.0 < 4.2.2, 4.0.0 < 4.1.7, < 3.6.12 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADP | 3.1 | 9.1 Critical | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H |
| redhat-SADP | 3.1 | 8.1 High | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N |
| GitHub | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: low (any account)
- User interaction: none
- Scope: unchanged
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none, automatable no, technical impact total.
- FIRST EPSS (model of 2026-10-21): 0.78% probability of exploitation activity in the next 30 days; percentile 55.
Timeline
- — CVE record published by apache
- — GitHub-reviewed advisory GHSA-9mrv-8pvf-hf4m published (critical)
- — CVE record last updated
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vendor and project advisories, patches
- lists.apache.org lists.apache.org
- access.redhat.com access.redhat.com
Vulnerability records
- GitHub Advisory GHSA-9mrv-8pvf-hf4m github.com
- CVE.org record CVE-2026-50627 cve.org
- NVD entry CVE-2026-50627 nvd.nist.gov
Other references from the CVE record and advisory
- openwall.com openwall.com
- access.redhat.com access.redhat.com
- RHBZ#2488298 bugzilla.redhat.com
- security.access.redhat.com security.access.redhat.com