What is CVE-2026-34876?

CVE-2026-34876 is a high-severity vulnerability in Trustedfirmware Mbed_tls, classified under Out-of-bounds Read. CVSS score: 7.5/10. Published 2026-04-02.

How severe is CVE-2026-34876?

High severity. CVSS v3 base score is 7.5 out of 10.

Out-of-bounds Read in Trustedfirmware Mbed_tls

CVE-2026-34876

An issue was discovered in Mbed TLS 3.x before 3.6.6. An out-of-bounds read vulnerability in mbedtls_ccm_finish() in library/ccm.c allows attackers to obtain adjacent CCM context data via invocation of the multipart CCM API with an oversiz…

Vulnerability class: Buffer Overflow

EPSS: 0.000 (7.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

Affected products

Trustedfirmware Mbed_tls
N/a — versions n/a

Weakness classification (CWE)

CWE-125 — Out-of-bounds Read

References

cve@mitre.org (Vendor Advisory)
cve@mitre.org (Vendor Advisory)

Frequently asked questions

What is CVE-2026-34876?: CVE-2026-34876 is a high-severity vulnerability in Trustedfirmware Mbed_tls, classified under Out-of-bounds Read. CVSS score: 7.5/10. Published 2026-04-02.
How severe is CVE-2026-34876?: High severity. CVSS v3 base score is 7.5 out of 10.