CVE-2026-2779Improper Restriction of Operations within the Bounds of a Memory Buffer in Mozilla Firefox

Severity
9.8CRITICALNVD
EPSS
0.1%
top 79.90%
CISA KEV
Not in KEV
Exploit
No known exploits
Timeline
PublishedFeb 24

Description

Incorrect boundary conditions in the Networking: JAR component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitability: 3.9 | Impact: 5.9

Affected Packages3 packages

NVDmozilla/firefox< 140.8.0+1
NVDmozilla/thunderbird< 140.8.0+1
Debianmozilla/thunderbird< 1:140.8.0esr-1~deb11u1+3

🔴Vulnerability Details

3
CVEList
Incorrect boundary conditions in the Networking: JAR component2026-02-24
OSV
CVE-2026-2779: Incorrect boundary conditions in the Networking: JAR component2026-02-24
GHSA
GHSA-94rx-4fcc-c849: Incorrect boundary conditions in the Networking: JAR component2026-02-24

📋Vendor Advisories

6
Red Hat
firefox: thunderbird: Incorrect boundary conditions in the Networking: JAR component2026-02-24
Debian
CVE-2026-2779: firefox - Incorrect boundary conditions in the Networking: JAR component. This vulnerabili...2026
Mozilla
Mozilla Foundation Security Advisory 2026-13: CVE-2026-2779
Mozilla
Mozilla Foundation Security Advisory 2026-15: CVE-2026-2779
Mozilla
Mozilla Foundation Security Advisory 2026-17: CVE-2026-2779

🕵️Threat Intelligence

1
Wiz
CVE-2026-2779 Impact, Exploitability, and Mitigation Steps | Wiz

💬Community

1
Bugzilla
CVE-2026-2779 firefox: thunderbird: Incorrect boundary conditions in the Networking: JAR component2026-02-24
CVE-2026-2779 — Mozilla Firefox vulnerability | cvebase