Buffer overflow in TF-PSA-Crypto and mbed TLS - CVE-2026-50584
Published: July 13, 2026
Vulnerability identifier: #VU137394
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-50584
CWE-ID: CWE-119
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to disclose sensitive information and forge messages.
The vulnerability exists due to improper restriction of operations within the bounds of a memory buffer in ChaCha20, ChaCha20-Poly1305, and PSA AEAD APIs when processing more than 256 GB of data with the same key and nonce or when using a starting counter and input length that cross the 32-bit counter range. A remote attacker can provide specially crafted oversized input or trigger counter wraparound to disclose sensitive information and forge messages.
Mbed TLS TLS protocol code is not affected because it does not expose a way to exceed the ChaCha20-Poly1305 record limits under a single key and nonce.
Affected software
TF-PSA-Crypto
mbed TLS
mbed TLS
How to mitigate CVE-2026-50584
Install security update from vendor's website.
TF-PSA-Crypto - addressed in versions 1.1.1, 1.2.0
mbed TLS - addressed in versions 3.6.7, 4.1.1, 4.2.0
mbed TLS - addressed in versions 3.6.7, 4.1.1, 4.2.0