Mozilla Firefox ESR up to 128.10 memory corruption

Summaryinfo

A vulnerability described as critical has been identified in Mozilla Firefox ESR up to 128.10. Affected is an unknown function. Such manipulation leads to memory corruption. This vulnerability is traded as CVE-2025-5269. The attack may be launched remotely. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Mozilla Firefox ESR up to 128.10. It has been rated as critical. Affected by this issue is an unknown code block. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Memory safety bug present in Firefox ESR 128.10, and Thunderbird 128.10. This bug showed evidence of memory corruption and we presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 128.11.

The advisory is shared for download at bugzilla.mozilla.org. This vulnerability is handled as CVE-2025-5269 since 05/27/2025. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 08/17/2025).

The vulnerability scanner Nessus provides a plugin with the ID 237297 (Mozilla Firefox ESR < 128.11), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 128.11 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (237297) and CERT Bund (WID-SEC-2025-1850). Once again VulDB remains the best source for vulnerability data.

Affected

• Xerox FreeFlow Print Server

Productinfo

Type

• Web Browser

Vendor

• Mozilla

Name

• Firefox ESR

Version

• 128.0
• 128.1
• 128.2
• 128.3
• 128.4
• 128.5
• 128.6
• 128.7
• 128.8
• 128.9
• 128.10

License

• open-source

Website

• Vendor: https://www.mozilla.org/

CPE 2.3info

• 🔍
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CPE 2.2info

• 🔍
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Entryinfo

Once again VulDB remains the best source for vulnerability data.

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