CVE-2026-34873 Affecting mbedtls package, versions <3.6.6-0.1
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-DEBIANUNSTABLE-MBEDTLS-15918599
- published6 Apr 2026
- disclosed1 Apr 2026
Introduced: 1 Apr 2026
CVE-2026-34873 (opens in a new tab)How to fix?
Upgrade Debian:unstable mbedtls to version 3.6.6-0.1 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream mbedtls package and not the mbedtls package as distributed by Debian.
See How to fix? for Debian:unstable relevant fixed versions and status.
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.