Vulnerability in Mozilla Firefox

CVE-2025-2857

Following the recent Chrome sandbox escape (CVE-2025-2783), various Firefox developers identified a similar pattern in our IPC code. A compromised child process could cause the parent process to return an unintentionally powerful handle, l…

EPSS: 0.019 (77.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-2857?
CVE-2025-2857 is a critical-severity vulnerability in Mozilla Firefox, classified under Exposure of Resource to Wrong Sphere. CVSS score: 10.0/10. Published 2025-03-27.
How severe is CVE-2025-2857?
Critical severity. CVSS v3 base score is 10.0 out of 10.
Is CVE-2025-2857 known to be exploited?
3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.