Vulnerability · Published Apr 1, 2026 · Assigned by mitre
CVE-2026-34871
Medium 6.7
In plain English
A medium-severity security flaw in the mbedtls package (Debian). There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 10% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)6.7Medium
Exploit odds (30 days)0.2%top 90.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
An issue was discovered in Mbed TLS before 3.6.6 and 4.x before 4.1.0 and TF-PSA-Crypto before 1.1.0. There is a Predictable Seed in a Pseudo-Random Number Generator (PRNG).
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | mbedtls | no fix listed | DEBIAN-CVE-2026-34871 |
| Debian:13 | mbedtls | no fix listed | DEBIAN-CVE-2026-34871 |
| Debian:14 | mbedtls | 3.6.6-0.1 | DEBIAN-CVE-2026-34871 |
| Ubuntu:25.10 | mbedtls | no fix listed | UBUNTU-CVE-2026-34871 |
| Ubuntu:26.04:LTS | mbedtls | no fix listed | UBUNTU-CVE-2026-34871 |
| Ubuntu:26.10 | mbedtls | no fix listed | UBUNTU-CVE-2026-34871 |
Affected products (as reported)
Weakness: CWE-338 · Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N