Improper Verification of Cryptographic Signature in Botan - CVE-2026-32883
Published: April 8, 2026
Vulnerability identifier: #VU125383
CSH Severity: Medium
CVSS v4: 8.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-32883
CWE-ID: CWE-347
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to bypass certificate revocation checks.
The vulnerability exists due to improper verification of cryptographic signature in OCSP response verification during X509 path validation when processing OCSP responses. A remote attacker can tamper with an OCSP response body to bypass certificate revocation checks.
Exploitation requires a machine-in-the-middle position between a Botan-based client and an OCSP responder.
Affected software
Botan
Fedora
botan3
Fedora
botan3
How to mitigate CVE-2026-32883
Install security update from vendor's website.
Botan - update to 3.11.0
botan3 - addressed in versions 3.9.0-3.el10_3, 3.9.0-4.el10_3, 3.9.0-6.fc44, 3.9.0-7.fc44
botan3 - addressed in versions 3.9.0-3.el10_3, 3.9.0-4.el10_3, 3.9.0-6.fc44, 3.9.0-7.fc44