Vulnerability Description
An issue was discovered in Mbed TLS versions from 2.19.0 up to 3.6.5, Mbed TLS 4.0.0. Insufficient protection of serialized SSL context or session structures allows an attacker who can modify the serialized structures to induce memory corruption, leading to arbitrary code execution. This is caused by Incorrect Use of Privileged APIs.
CVSS Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Arm | Mbed Tls | >= 2.19.0, < 3.6.6 |
Related Weaknesses (CWE)
References
- https://mbed-tls.readthedocs.io/en/latest/security-advisories/Vendor Advisory
- https://mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-security-aVendor Advisory
FAQ
What is CVE-2026-34877?
CVE-2026-34877 is a vulnerability with a CVSS score of 9.8 (CRITICAL). An issue was discovered in Mbed TLS versions from 2.19.0 up to 3.6.5, Mbed TLS 4.0.0. Insufficient protection of serialized SSL context or session structures allows an attacker who can modify the seri...
How severe is CVE-2026-34877?
CVE-2026-34877 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-34877?
Check the references section above for vendor advisories and patch information. Affected products include: Arm Mbed Tls.