SB2026042872 - Stack-based buffer overflow in HarfBuzz
Published: April 28, 2026
Security Bulletin ID
SB2026042872
Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Stack-based buffer overflow (CVE-ID: N/A)
The vulnerability allows a remote attacker to overwrite other data.
The vulnerability exists due to a stack-based buffer overflow in debug messaging in Sequence.hh when processing a maliciously crafted OpenType font with a GSUB sequence lookup. A remote attacker can supply a crafted font that injects a large number of glyphs to overwrite other data.
The issue is reachable only when debug messaging is enabled using hb_buffer_set_message_func.
Remediation
Install update from vendor's website.