SB2026021227 - Ubuntu update for libtasn1-6 



SB2026021227 - Ubuntu update for libtasn1-6

Published: February 12, 2026

Security Bulletin ID SB2026021227
Severity
Medium
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 2 secuirty vulnerabilities.


1) Off-by-one (CVE-ID: CVE-2021-46848)

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to an ETYPE_OK off-by-one error in asn1_encode_simple_der in Libtasn1. A remote attacker can pass specially crafted data to the application, trigger an off-by-one error and perform a denial of service (DoS) attack.


2) Stack-based buffer overflow (CVE-ID: CVE-2025-13151)

The vulnerability allows a remote attacker to perform a denial of service attack.

The vulnerability exists due to a boundary error within the asn1_expend_octet_string() function. A remote attacker can pass specially crafted certificate to the application, trigger a stack-based buffer overflow and perform a denial of service attack..



Remediation

Install update from vendor's website.