CVE-2026-55956
MEDIUM 6.5Improper Authorization vulnerability in Apache Tomcat leads to security constraints specified for the default servlet ignoring any method or method omission configured as part of the constraint. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.0.M1 through 9.0.118, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Other versions that have reached end of support may also be affected. Users are recommended to upgrade to version 11.0.23, 10.1.56 or 9.0.119, which fix the issue.
No known exploitation, public exploit, or elevated probability at this time. Track for changes.
Exploitation likelihood
0.4%chance of exploitation in 30 days · 33rd percentile
Impact if exploited
6.5CVSS 3.1 · MEDIUM
- ConfidentialityLow
- IntegrityLow
- AvailabilityNone
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ✓Privileges: No account or privileges required
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-55956/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-55956/poc.json
Weakness (CWE)
- CWE-285: Improper Authorization
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Known Affected Software Configurations
| Vendor | Product | Version range |
|---|---|---|
| Apache | Tomcat | < 9.0.119 |
| Apache | Tomcat | ≥ 10.1.0 and < 10.1.56 |
| Apache | Tomcat | ≥ 11.0.0 and < 11.0.23 |
All CVSS metrics
- MEDIUM 6.5 v3.1 · ADP Primary
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - MEDIUM 6.5 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N