Critical· 9.3official fix available
CVE-2026-34580
Botan 3.11.0 had a certificate validation flaw where it could mistakenly accept an end entity certificate as a trusted root if its DN matched any trusted root. This was fixed in Botan 3.11.1.
publishedApr 7, 2026
last modifiedJul 24, 2026
sourcesNVD
severity · cvss
9.3
critical · how bad it is
exploitation · epss
<1%
16th percentile · chance of exploitation in 30 days
(ai-assisted) A model wrote this summary from the official data, so double-check it against the source before you act on it. Read the official advisory →
auto-deletes from the system
counting…on Aug 25, 2026
An official fix is available, so this entry is kept for 30 days and then removed automatically.
01
Who is affected
Users of Botan 3.11.0
02
Real-world impact
Attackers could impersonate trusted authorities by presenting certificates with matching DN/SKI, bypassing security checks.
03
Why this severity
Critical (CVSS 9.3) - High risk of unauthorized trust establishment leading to potential man-in-the-middle attacks.
04
What to do about it
official fix available
recommended steps
- 01Upgrade Botan to version 3.11.1 or later.
NVD-referenced vendor advisory
05
Timeline
- Apr 7, 2026 · Apr 7, 2026PublishedDisclosed and added to the National Vulnerability Database.
- Jul 24, 2026 · 11d agoAdvisory updatedThe NVD record was last revised.
- Jul 26, 2026 · 10d agoOfficial fix availableA vendor patch or mitigation now exists — see the remediation steps above.
06
How it’s attacked
Attack vectorNetwork (remote)
Attack complexityLow
Attack requirementsNone
Privileges requiredNone
User interactionNone needed
Confidentiality impactHigh
Integrity impactHigh
Availability impactHigh
07
(ai-assisted) A model wrote this summary from the official data, so double-check it against the source before you act on it. Read the official advisory →