CVE-2026-34873
9.1
CRITICAL
CVSS 3.1
EPSS 0.04%
Description
An issue was discovered in Mbed TLS 3.5.0 through 4.0.0. Client impersonation can occur while resuming a TLS 1.3 session.
How to fix CVE-2026-34873
No fixed version has been published yet. Mitigate by removing the affected package or applying upstream guidance from the references below.
- Debian/mbedtls—no fix listed
Is CVE-2026-34873 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | CRITICAL9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |