CVE-2026-32883 PUBLISHED

Botan: Missing OCSP Response Signature Verification Allows MitM Certificate Revocation Bypass

Assigner: GitHub_M
Reserved: 16.03.2026 Published: 30.03.2026 Updated: 30.03.2026

Botan is a C++ cryptography library. From version 3.0.0 to before version 3.11.0, during X509 path validation, OCSP responses were checked for an appropriate status code, but critically omitted verifying the signature of the OCSP response itself. This issue has been patched in version 3.11.0.

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
CVSS Score: 5.9

Attack Vector	Network	Scope	Unchanged
Attack Complexity	High	Confidentiality Impact	None
Privileges Required	None	Integrity Impact	High
User Interaction	None	Availability Impact	None

CVSS 3.1

Product Status

Vendor	randombit
Product	botan
Versions	Version >= 3.0.0, < 3.11.0 is affected

References

https://github.com/randombit/botan/security/advisories/GHSA-9j2j-hqmc-hf5x

Problem Types

CWE-347: Improper Verification of Cryptographic Signature CWE