SB20260408180 - Debian update for firefox-esr

Description

This security bulletin contains information about 3 secuirty vulnerabilities.

1) Buffer overflow (CVE-ID: CVE-2026-5731)

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error when processing HTML content. A remote attacker can trick the victim into visiting a specially crafted website, trigger memory corruption and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

2) Integer overflow (CVE-ID: CVE-2026-5732)

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to integer overflow in the Graphics: Text component. A remote attacker can trick the victim into visiting a specially crafted website, trigger an integer overflow and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

3) Buffer overflow (CVE-ID: CVE-2026-5734)

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error when processing HTML content. A remote attacker can trick the victim into visiting a specially crafted website, trigger memory corruption and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Remediation

Install update from vendor's website.

References

• https://lists.debian.org/debian-security-announce/2026/msg00112.html