CVE-2026-4687HIGH 8.6EPSS p34.2%

CVE-2026-4687CVE-2026-4687

Description

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

Scoring

CVSS 3.18.6 (HIGH)
VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
EPSS0.43% probability of exploitation · percentile 34.2% · 2026-06-19T12:03:05Z
Published2026-03-24
Last modified2026-04-13

Underlying weaknesses· 2

CWE-754CWE-120

References

  1. https://bugzilla.mozilla.org/show_bug.cgi?id=2016368
  2. https://www.mozilla.org/security/advisories/mfsa2026-20/
  3. https://www.mozilla.org/security/advisories/mfsa2026-21/
  4. https://www.mozilla.org/security/advisories/mfsa2026-22/
  5. https://www.mozilla.org/security/advisories/mfsa2026-23/
  6. https://www.mozilla.org/security/advisories/mfsa2026-24/

2

TypeTargetConfidenceTier
WeaknessBuffer Copy without Checking Size of Input ('Classic Buffer Overflow')cwe-1200%live
WeaknessImproper Check for Unusual or Exceptional Conditionscwe-7540%live

Related by meaning· 6

Nearest entities by semantic similarity across the cs-graph corpus.

CVE
CVE-2026-2776
CVE
CVE-2026-4689
CVE
CVE-2026-2778
CVE
CVE-2026-4690
CVE
CVE-2026-2760
CVE
CVE-2026-4692
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.