CVE-2025-2857

EUVD-2025-8495

27.03.2025, 14:15

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, leading to a sandbox escape. 
The original vulnerability was being exploited in the wild. 
*This only affects Firefox on Windows. Other operating systems are unaffected.*. This vulnerability was fixed in Firefox 136.0.4, Firefox ESR 128.8.1, and Firefox ESR 115.21.1.

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
NIST	Primary	10 CRITICAL	NETWORK	LOW	NONE	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Base Score

CVSS 3.x

EPSS Score

Percentile: Unknown

Affected Products (NVD)

Vendor	Product	Version
mozilla	firefox	𝑥 < 136.0.4
mozilla	firefox_esr	𝑥 < 115.21.1
mozilla	firefox_esr	128.1.0 ≤ 𝑥 < 128.8.1

𝑥

= Vulnerable software versions

Debian Releases

Debian Product

Codename

firefox

sid	149.0.2-1 fixed

firefox-esr

bookworm	128.14.0esr-1~deb12u1 fixed
bookworm (security)	140.9.1esr-1~deb12u1 fixed
bullseye	115.14.0esr-1~deb11u1 fixed
bullseye (security)	140.9.1esr-1~deb11u1 fixed
forky	140.9.1esr-1 fixed
sid	140.9.1esr-1 fixed
trixie	140.8.0esr-1~deb13u1 fixed
trixie (security)	140.9.1esr-1~deb13u1 fixed

Common Weakness Enumeration

CWE-668 - Exposure of Resource to Wrong Sphere
The product exposes a resource to the wrong control sphere, providing unintended actors with inappropriate access to the resource.

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1956398

https://issues.chromium.org/issues/405143032

https://www.cve.org/CVERecord?id=CVE-2025-2783

https://www.mozilla.org/security/advisories/mfsa2025-19/