SB2026010599 - Ubuntu update for webkit2gtk



SB2026010599 - Ubuntu update for webkit2gtk

Published: January 5, 2026

Security Bulletin ID SB2026010599
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 4
Exploitation vector Remote access
Highest impact Partial DoS

Breakdown by Severity

Medium 25% Low 75%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 4 vulnerabilities.


1) Buffer overflow (CVE-ID: CVE-2025-66287)

CWE-ID: CWE-119 - Memory corruption

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a remote attacker to crash the browser.

The vulnerability exists due to a boundary error when HTML content in WebKit. A remote attacker can trick the victim into visiting a specially crafted website, trigger memory corruption and crash the browser.


2) Input validation error (CVE-ID: CVE-2025-43458)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear


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

The vulnerability exists due to insufficient validation of user-supplied input in WebKit. A remote attacker can trick the victim into opening a specially crafted web page and crash the browser.


3) Buffer overflow (CVE-ID: CVE-2025-43421)

CWE-ID: CWE-119 - Memory corruption

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear


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

The vulnerability exists due to a boundary error in WebKit. A remote attacker can trick the victim into visiting a specially crafted website, trigger memory corruption and crash the browser.


4) Information disclosure (CVE-ID: CVE-2025-13947)

CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green


The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to excessive data output in WebKit. A remote attacker can trick the victim into visiting a specially crafted website and exfiltrate system information. 


Remediation

Install update from vendor's website.