CVE-2025-13151
Published: 07 January 2026
Summary
CVE-2025-13151 is a high-severity Out-of-bounds Write (CWE-787) vulnerability in Gnu Libtasn1. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 23.5th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
Threat & Defense at a Glance
Threat & Defense Details
Likely Mitigating ControlsAI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Out-of-bounds writes that corrupt control flow or inject shellcode are rendered non-executable by the same memory protections.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Stack buffer overflow in network-reachable library directly enables remote application/system crash for DoS via exploitation (CWE-787, CVSS A:H only).
NVD Description
Stack-based buffer overflow in libtasn1 version: v4.20.0. The function fails to validate the size of input data resulting in a buffer overflow in asn1_expend_octet_string.
Deeper analysisAI
CVE-2025-13151 is a stack-based buffer overflow vulnerability (CWE-787) in libtasn1 version 4.20.0. The flaw resides in the asn1_expend_octet_string function, which fails to validate the size of input data, resulting in a buffer overflow. This affects the libtasn1 library, a component used for ASN.1 structure management and commonly integrated into projects like GnuTLS.
The vulnerability carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H), indicating high severity due to its network accessibility, low attack complexity, and lack of requirements for privileges or user interaction. Remote, unauthenticated attackers can exploit it over the network to trigger a denial-of-service condition, such as crashing affected applications, with no impact on confidentiality or integrity.
Advisories and patches are referenced in the libtasn1 GitLab repository and merge request 121, which likely contains the fix. Further details appear in the oss-security mailing list post from January 8, 2026, and CERT vulnerability note 271649. Security practitioners should review these sources for patching instructions and verify updates in dependent software.
Details
- CWE(s)