PT-2026-33935 · Mozilla+1 · Firefox+2

Inseo An · Published 2026-04-21 · Updated 2026-05-19 · CVE-2026-6749

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Name of the Vulnerable Software and Affected Versions Firefox versions prior to 150 Firefox ESR versions prior to 115.35 Firefox ESR versions prior to 140.10 Thunderbird versions prior to 150 Thunderbird versions prior to 140.10

Description Information disclosure occurs due to uninitialized memory in the Graphics: Canvas2D component.

Recommendations Update Firefox to version 150. Update Firefox ESR to version 115.35. Update Firefox ESR to version 140.10. Update Thunderbird to version 150. Update Thunderbird to version 140.10.

Fix

DoS

Use of Uninitialized Resource

Weakness Enumeration

CWE-908

Related Identifiers

ALSA-2026:10757

ALSA-2026:10766

ALSA-2026:10767

ALSA-2026:12285

ALSA-2026:13537

ALSA-2026:15892

ALSA-2026:19348

CVE-2026-6749

OESA-2026-2105

OESA-2026-2106

OESA-2026-2107

OESA-2026-2108

OESA-2026-2109

OPENSUSE-SU-2026:10610-1

OPENSUSE-SU-2026:10626-1

RHSA-2026:10757

RHSA-2026:10766

RHSA-2026:10767

RHSA-2026:19348

Affected Products

Firefox

Rocky Linux

Thunderbird

References · 194

• https://osv.dev/vulnerability/DEBIAN-CVE-2026-6749 · Vendor Advisory
• https://mozilla.org/en-US/security/advisories/mfsa2026-32 · Vendor Advisory
• https://mozilla.org/en-US/security/advisories/mfsa2026-30/#CVE-2026-6749 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-6766 · Security Note
• https://mozilla.org/security/advisories/mfsa2026-31 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-6754 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-6759 · Security Note
• https://mozilla.org/security/advisories/mfsa2026-33 · Vendor Advisory
• https://osv.dev/vulnerability/openSUSE-SU-2026:10626-1 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-6765 · Security Note
• https://errata.rockylinux.org/RLSA-2026:10757 · Vendor Advisory
• https://errata.almalinux.org/9/ALSA-2026-10757.html · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-6749 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2026-6749 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-5732 · Security Note