Medium severity · published Jul 4, 2025
CVE-2025-52497
Mbed TLS before 3.6.4 has a PEM parsing one-byte heap-based buffer underflow, in mbedtls_pem_read_buffer and two mbedtls_pk_parse functions, via untrusted PEM input
4.8
CVSS
0.3%
EPSS
No
On KEV
Description
Mbed TLS before 3.6.4 has a PEM parsing one-byte heap-based buffer underflow, in mbedtls_pem_read_buffer and two mbedtls_pk_parse functions, via untrusted PEM input.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 26% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MB
mbedtls · Mbed
before 3.6.4 · source: vendor
MT
Mbed Tls · Arm
before 3.6.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-52497
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-52497
Third Party Advisory
https://github.com/Mbed-TLS/mbedtls-docs/blob/main/security-advisories/mbedtls-security-advisory-2025-06-2.md
lists.debian.org
https://lists.debian.org/debian-lts-announce/2025/08/msg00013.html
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