CVE-2025-2857 Incorrect handle could lead to sandbox escapes

What is CVE-2025-2857?

CVE-2025-2857 is a critical vulnerability in Mozilla Firefox, published on 27 Mar 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

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.

Weakness: CWE-668

Which versions are affected by CVE-2025-2857?

It affects 1 product.

Products include Mozilla Firefox.

How do I fix CVE-2025-2857?

Upgrade to a fixed version.

Is CVE-2025-2857 being exploited?

There is no known exploitation of CVE-2025-2857 in the wild and no public exploit code.

Other vulnerabilities in Mozilla Firefox

• CVE-2019-11708 Mozilla Firefox and Thunderbird Sandbox Escape Exploited Critical 10.0
• CVE-2010-3765 Mozilla Multiple Products Remote Code Execution Exploited Critical 9.8
• CVE-2022-26486 Mozilla Firefox Use-After-Free Exploited Critical 9.6
• CVE-2022-26485 Mozilla Firefox Use-After-Free Exploited High 8.8
• CVE-2019-11707 Mozilla Firefox and Thunderbird Type Confusion Exploited High 8.8

All Mozilla Firefox vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-h8g5-2596-xjh9, openSUSE-SU-2025:14948-1.