Auth bypass in Apache Tomcat
CVE-2026-43515
Improper Authorization vulnerability when multiple method constraints define an HTTP method for the same extension in Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.21, from 10.1.0-M1 through 10.1.54, from 9.0.0.M1 through 9.0.117, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Users are recommended to upgrade to version 11.0.22, 10.1.55 or 9.0.118 which fix the issue.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.012 (67.5th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 68th percentile — 67.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.011 · newest: 0.012 · change: +0.001
Affected products
- Apache Tomcat
- Apache Software Foundation Tomcat — versions 11.0.0-M1, 10.1.0-M1, 9.0.0.M1
Weakness classification (CWE)
Public proof-of-concept exploits
References
- lists.apache.org/thread/746nxfxod0wsocxtmv8pb8nkgmwpc6bb (vendor-advisory, Mailing List, Vendor Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-43515?
- CVE-2026-43515 is a critical-severity vulnerability in Apache Tomcat, classified under Improper Authorization. CVSS score: 9.1/10. Published 2026-05-12.
- How severe is CVE-2026-43515?
- Critical severity. CVSS v3 base score is 9.1 out of 10.
- Is CVE-2026-43515 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.