CVE-2026-50629
MEDIUMCVE-2026-50629 is a medium-severity (CVSS 5.3) CWE-93 vulnerability in org.apache.cxf:cxf-rt-rs-security-oauth2. O3 Security confirms whether CVE-2026-50629 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Apache CXF: OAuth2: Log Injection via Unsanitized Client Identifier
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-50629.
Real-World Exposure
org.apache.cxf:cxf-rt-rs-security-oauth2☕org.apache.cxf:cxf-rt-rs-security-oauth2Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
The 'clientId' parameter from incoming HTTP requests is directly concatenated into OAuth2 server log warning messages without sanitizing control characters. This allows an attacker to inject arbitrary content, including fake log entries, into the server's log files. Users are recommended to upgrade to versions 4.2.2 or 4.1.7 or 3.6.12, which fixes this issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕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 | all versions | 4.1.7 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.cxf:cxf-rt-rs-security-oauth2. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update org.apache.cxf:cxf-rt-rs-security-oauth2 to 4.2.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-50629 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-50629 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-50629. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-50629 in your dependencies?
O3 detects CVE-2026-50629 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.