#VU112443 Covert Timing Channel in mbed TLS - CVE-2025-49087
Published: July 7, 2025
Vulnerability identifier: #VU112443
Vulnerability risk: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2025-49087
CWE-ID: CWE-385
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
mbed TLS
mbed TLS
Software vendor:
ARM
ARM
Description
The vulnerability allows a remote attacker to perform MitM attack.
The vulnerability exists due to a timing side channel attack on its implementation of PKCS#7 padding removal. A remote attacker with access to timing information and a decryption oracle can recover the last byte of each plaintext block. If some portion of the plaintext is controlled by the attacker as is often the case, the whole plaintext can be recovered.
Remediation
Install updates from vendor's website.