Incorrect Behavior Order: Validate Before Canonicalize in Apache Tomcat - CVE-2026-59083
Published: July 14, 2026
Vulnerability identifier: #VU137408
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-59083
CWE-ID: CWE-180
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Apache Foundation
Affected software:
Apache Tomcat
Apache Tomcat
Detailed vulnerability description
The vulnerability allows a remote attacker to bypass security controls.
The vulnerability exists due to incorrect URL decoding in RewriteValve when processing rewritten URIs. A remote attacker can send a specially crafted request to bypass security controls.
Only some configurations are vulnerable.
How to mitigate CVE-2026-59083
Install security update from vendor's website.
Sources
- https://tomcat.apache.org/security-10.html#Fixed_in_Apache_Tomcat_10.1.57
- https://github.com/apache/tomcat/commit/04e9ec3d32209faa26ca6c23ebd9ad514690aec0
- https://tomcat.apache.org/security-11.html#Fixed_in_Apache_Tomcat_11.0.24
- https://tomcat.apache.org/security-9.html#Fixed_in_Apache_Tomcat_9.0.120