Critical Denial of Service Vulnerability in libtasn1: CVE-2025-13151
Summary
RLSA-2026:36728: Low: libtasn1 security update. Affects libtasn1 versions < 0:4.13-6.el8_10. Fixed in 0:4.13-6.el8_10. How to fix ↓
Check if this vulnerability affects your application
Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.
No signup required · Results in about 60 seconds
Background
libtasn1 is a library that facilitates the parsing and management of Abstract Syntax Notation One (ASN.1) structures, as well as encoding and decoding functions for Distinguished Encoding Rules (DER). It is widely used in various applications that require ASN.1 data handling. The library's functionality is crucial for applications that rely on secure communications and data formats, making it essential for maintaining data integrity and security.
Vulnerability Detail
The vulnerability identified as CVE-2025-13151 is a Denial of Service (DoS) issue caused by a stack-based buffer overflow in the function asn1_expend_octet_string. This flaw allows an attacker to exploit the library by sending specially crafted input, which can lead to application crashes or unresponsive behavior. The potential ramifications include service interruptions and compromised application availability, which can significantly impact users relying on the affected software.
How To Fix
Minimum fixed version
0:4.13-6.el8_10
This is the first release that contains the fix.
sudo dnf update libtasn1Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
As a temporary workaround, you can limit the input size to the asn1_expend_octet_string function to prevent the overflow from occurring. However, this is not a permanent solution and updating the package is strongly advised.
Conclusion
The libtasn1 library has a critical vulnerability (CVE-2025-13151) that can lead to Denial of Service attacks. It is essential to update to the patched version to mitigate risks associated with this vulnerability. Regular monitoring and updates are crucial for maintaining application security.
See every vulnerability recorded for libtasn1 →
FAQ
CVE-2025-13151 is a vulnerability in the libtasn1 library that allows for a Denial of Service attack via a stack-based buffer overflow.
You can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without needing to sign up.
The primary risk is a Denial of Service, which can lead to application crashes and unavailability, affecting users and services relying on the affected software.
Yes, a patched version of libtasn1 (0:4.13-6.el8_10) is available. Updating to this version will resolve the vulnerability.
The CVSS score for this vulnerability is 5.9, indicating a moderate severity level.
Related vulnerabilities
Recent vulnerabilities recorded for libtasn1.
