Mozilla Firefox ESR up to 115.23.0 Javascript Object out-of-bounds write

Summaryinfo

A vulnerability classified as critical has been found in Mozilla Firefox ESR up to 115.23.0. This impacts an unknown function of the component Javascript Object Handler. Performing a manipulation results in out-of-bounds write. This vulnerability was named CVE-2025-4919. The attack may be initiated remotely. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Mozilla Firefox ESR up to 115.23.0. This affects some unknown processing of the component Javascript Object Handler. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. CWE is classifying the issue as CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

An attacker was able to perform an out-of-bounds read or write on a JavaScript object by confusing array index sizes. This vulnerability affects Firefox ESR < 115.23.1.

It is possible to read the advisory at bugzilla.mozilla.org. This vulnerability is uniquely identified as CVE-2025-4919 since 05/17/2025. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 08/16/2025).

The vulnerability scanner Nessus provides a plugin with the ID 236893 (Mozilla Firefox ESR < 115.23.1), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 115.23.1 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (236893), EUVD (EUVD-2025-15598) and CERT Bund (WID-SEC-2025-1850). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Xerox FreeFlow Print Server

Productinfo

Type

• Web Browser

Vendor

• Mozilla

Name

• Firefox ESR

Version

• 115.0
• 115.1
• 115.2
• 115.3
• 115.4
• 115.5
• 115.6
• 115.7
• 115.8
• 115.9
• 115.10
• 115.11
• 115.12
• 115.13
• 115.14
• 115.15
• 115.16
• 115.17
• 115.18
• 115.19
• 115.20
• 115.21
• 115.22
• 115.23.0

License

• open-source

Website

• Vendor: https://www.mozilla.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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