JLSEC-2025-229 Medium 4.8

Mbed TLS before 3.6.4 has a PEM parsing one-byte heap-based buffer underflow, in...

JLSEC Published: Nov 21, 2025
Modified: Jul 23, 2026
Severity: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Affected Packages: MbedTLS_jll < 2.28.1010+0
Upstream: CVE-2025-52497

Mbed TLS before 3.6.4 has a PEM parsing one-byte heap-based buffer underflow, in mbedtls_pem_read_buffer and two mbedtls_pk_parse functions, via untrusted PEM input.

References

https://github.com/Mbed-TLS/mbedtls-docs/blob/main/security-advisories/mbedtls-security-advisory-2025-06-2.md
https://lists.debian.org/debian-lts-announce/2025/08/msg00013.html