CVE-2026-4687

CWE-754CWE-120 — Classic Buffer OverflowCWE-50113 documents9 sources
Severity
8.6HIGH
EPSS
0.0%
top 93.56%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
3
Mozilla FirefoxMozilla Firefox ESRMozilla Thunderbird
Timeline
PublishedMar 24

Description

Sandbox escape due to incorrect boundary conditions in the Telemetry component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:HExploitability: 3.9 | Impact: 4.0

Affected Packages6 packages

▶CVEListV5mozilla/firefoxunspecified — 149
▶NVDmozilla/firefox128.0 — 140.9.0+2
▶CVEListV5mozilla/firefox_esrunspecified — 115.34+1
▶Debianfirefox-esr< 140.9.0esr-1~deb11u1+3
▶CVEListV5mozilla/thunderbirdunspecified — 149+1

🔴Vulnerability Details

3
CVEList
Sandbox escape due to incorrect boundary conditions in the Telemetry component↗2026-03-24
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OSV
CVE-2026-4687: Sandbox escape due to incorrect boundary conditions in the Telemetry component↗2026-03-24
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GHSA
GHSA-gw7x-g9xx-wmm2: Sandbox escape due to incorrect boundary conditions in the Telemetry component↗2026-03-24
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📋Vendor Advisories

7
Red Hat
firefox: thunderbird: Sandbox escape due to incorrect boundary conditions in the Telemetry component↗2026-03-24
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Debian
CVE-2026-4687: firefox - Sandbox escape due to incorrect boundary conditions in the Telemetry component. ...↗2026
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Mozilla
Mozilla Foundation Security Advisory 2026-22: CVE-2026-4687↗
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Mozilla
Mozilla Foundation Security Advisory 2026-23: CVE-2026-4687↗
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Mozilla
Mozilla Foundation Security Advisory 2026-24: CVE-2026-4687↗
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🕵️Threat Intelligence

1
Wiz
CVE-2026-4687 Impact, Exploitability, and Mitigation Steps | Wiz↗
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💬Community

1
Bugzilla
CVE-2026-4687 firefox: thunderbird: Sandbox escape due to incorrect boundary conditions in the Telemetry component↗2026-03-24
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