Medium severity · published Oct 21, 2025
CVE-2025-59438
Mbed TLS through 3.6.4 has an Observable Timing Discrepancy
5.3
CVSS
0.3%
EPSS
No
On KEV
Description
Mbed TLS through 3.6.4 has an Observable Timing Discrepancy.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 18% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MT
Mbed Tls · Arm
before 3.6.5 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-59438
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-59438
Vendor Advisory
https://mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-security-advisory-2025-10-invalid-padding-error/
Vendor Advisory
https://mbed-tls.readthedocs.io/en/latest/tech-updates/security-advisories/
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