PT-2026-49675 · Mozilla+1 · Firefox Esr+3

Mihalis Haatainen · CVE-2026-12306 · Published 2026-06-16 · Updated 2026-07-10

Positive Technologies (AI Summary)

CVSS v3.1

5.3

Medium

Base vector

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

Name of the Vulnerable Software and Affected Versions Firefox versions prior to 152 Firefox ESR versions prior to 140.12 Thunderbird versions prior to 152 Thunderbird versions prior to 140.12

Description A memory safety bug exists in the software, which could lead to unexpected behavior or crashes when handling memory operations.

Recommendations Update Firefox to version 152. Update Firefox ESR to version 140.12. Update Thunderbird to version 152. Update Thunderbird to version 140.12.

Fix

DoS

Buffer Overflow

Weakness Enumeration

CWE-119

Related Identifiers

ALSA-2026:27717

ALSA-2026:27733

ALSA-2026:27734

ALSA-2026:29940

ALSA-2026:30846

ALSA-2026:33445

CVE-2026-12306

OESA-2026-2735

OPENSUSE-SU-2026:11052-1

OPENSUSE-SU-2026:11055-1

OPENSUSE-SU-2026:11072-1

OPENSUSE-SU-2026:21043-1

OPENSUSE-SU-2026:21168-1

RHSA-2026:33445

SUSE-SU-2026:22351-1

SUSE-SU-2026:2582-1

SUSE-SU-2026:2583-1

SUSE-SU-2026:2814-1

SUSE-SU-2026:2852-1

Affected Products

Firefox

Firefox Esr

Rocky Linux

Thunderbird

References · 226

• https://osv.dev/vulnerability/SUSE-SU-2026:22351-1 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-12315 · Security Note
• https://mozilla.org/en-US/security/advisories/mfsa2026-57/#CVE-2026-12306 · Vendor Advisory
• https://mozilla.org/security/advisories/mfsa2026-58/#CVE-2026-12306 · Vendor Advisory
• https://mozilla.org/en-US/security/advisories/mfsa2026-58 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-12325 · Security Note
• https://osv.dev/vulnerability/openSUSE-SU-2026:11055-1 · Vendor Advisory
• https://osv.dev/vulnerability/openSUSE-SU-2026:11052-1 · Vendor Advisory
• https://osv.dev/vulnerability/ALSA-2026:27717 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2026-12306 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-12289 · Security Note
• https://osv.dev/vulnerability/openSUSE-SU-2026:21168-1 · Vendor Advisory
• https://mozilla.org/en-US/security/advisories/mfsa2026-61/#CVE-2026-12306 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-12329 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-12290 · Security Note