CVE-2026-34580 | randombit botan up to 3.11.0 Path Validation certificate_known certificate validation

VDB-355957 · CVE-2026-34580 · GCVE-0-2026-34580 RANDOMBIT BOTAN UP TO 3.11.0 PATH VALIDATION CERTIFICATE_KNOWN CERTIFICATE VALIDATION HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 3.6 $0-$5k 2.77 Summaryinfo A vulnerability was found in randombit botan up to 3.11.0. It has been rated as critical. This affects the function Certificate_Store::certificate_known of the component Path Validation Handler. This manipulation causes certificate validation. This vulnerability is tracked as CVE-2026-34580. The attack is possible to be carried out remotely. No exploit exists. Upgrading the affected component is advised. Detailsinfo A vulnerability was found in randombit botan up to 3.11.0. It has been declared as problematic. Affected by this vulnerability is the function Certificate_Store::certificate_known of the component Path Validation Handler. The manipulation with an unknown input leads to a certificate validation vulnerability. The CWE definition for the vulnerability is CWE-295. The product does not validate, or incorrectly validates, a certificate. As an impact it is known to affect integrity. The summary by CVE is: Botan is a C++ cryptography library. In 3.11.0, the function Certificate_Store::certificate_known had a misleading name; it would return true if any certificate in the store had a DN (and subject key identifier, if set) matching that of the argument. It did not check that the cert it found and the cert it was passed were actually the same certificate. In 3.11.0 an extension of path validation logic was made which assumed that certificate_known only returned true if the certificates were in fact identical. The impact is that if an end entity certificate is presented, and its DN (and subject key identifier, if set) match that of any trusted root, the end entity certificate is accepted immediately as if it itself were a trusted root. , This vulnerability is fixed in 3.11.1. The advisory is shared at github.com. This vulnerability is known as CVE-2026-34580 since 03/30/2026. The exploitation appears to be difficult. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1587.003 for this issue. Upgrading to version 3.11.1 eliminates this vulnerability. Productinfo Vendor randombit Name botan Version 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11.0 License open-source Website Product: https://github.com/randombit/botan/ CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA CVSS-B Score: 🔒 CNA CVSS-BT Score: 🔒 CNA Vector: 🔒 CVSSv3info VulDB Meta Base Score: 3.7 VulDB Meta Temp Score: 3.6 VulDB Base Score: 3.7 VulDB Temp Score: 3.6 VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Certificate validation CWE: CWE-295 / CWE-287 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: Upgrade Status: 🔍 0-Day Time: 🔒 Upgrade: botan 3.11.1 Timelineinfo 03/30/2026 CVE reserved 04/07/2026 +8 days Advisory disclosed 04/07/2026 +0 days VulDB entry created 04/07/2026 +0 days VulDB entry last update Sourcesinfo Product: github.com Advisory: github.com Status: Confirmed CVE: CVE-2026-34580 (🔒) GCVE (CVE): GCVE-0-2026-34580 GCVE (VulDB): GCVE-100-355957 Entryinfo Created: 04/07/2026 23:34 Changes: 04/07/2026 23:34 (68) Complete: 🔍 Cache ID: 99:A4A:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸