CVE-2026-34871: arm mbed_tls
CVSS: 6.7v3.1MediumAnalyzed
AliasesUBUNTU-CVE-2026-34871DEBIAN-CVE-2026-34871
Published 01-04-2026Last modified 01-04-2026
Vulnerability summary
CVE-2026-34871 is a medium (CVSS 6.7) vulnerability in arm mbed_tls. EPSS estimates a 0.15% chance of exploitation in the next 30 days, higher than 3.9% of scored vulnerabilities.
CVSS score
6.7/10
010
Medium · v3.1 (CVE.org)EPSS score
0.15%
0%100%
Low · -0.04 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 1 · Related 1Timeline
- 01-04-2026PublishedVulnerability first disclosed.
- 01-04-2026Last modifiedVulnerability information updated.
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).
CVSS metrics
4 scores · 4 sources · 1 versionMedium 6.7Preferred score · CVE.org (CNA)
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:NSourcesAll 4 agree
- OSV · UbuntuEcosystem advisory · calculated6.7MediumCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
- OSV · DebianEcosystem advisory · calculated6.7MediumCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
- NVDNIST6.7MediumCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS trend
Probability
0.15%
Chance of exploitation in the next 30 days
Percentile
4%
Versus all other CVEs
30-day change
-0.04 pp
From 0.19% on 20-09-2026
20-09-202620-10-2026
EPSS score0.15%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Arm1 product
- mbed_tls< 3.6.6
Debian1 product
- mbedtlsAll versions (No fix recorded) | < 3.6.6-0.1
Trustedfirmware1 product
- tf-psa-crypto< 1.1.0
Ubuntu1 product
- mbedtlsAll versions (No fix recorded)
4 vendors · 4 products
References
5 links- mbed-tls.readthedocs.io/en/latest/security-advisories/Vendor Advisory
