CVE-2025-51495: mongoose Integer Overflow

Description

An integer overflow vulnerability exists in the WebSocket component of Mongoose 7.5 thru 7.17. By sending a specially crafted WebSocket request, an attacker can cause the application to crash. If downstream vendors integrate this component improperly, the issue may lead to a buffer overflow.

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CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-190 Integer Overflow

Affected Products

Vendor	Product	Versions
cesanta	mongoose	7.5 — 7.17

References

Advisories & Patches

https://github.com/cesanta/mongoose/pull/3131

Exploits

https://github.com/cainiao159357/CVE-2025-51495

Other References

https://github.com/cesanta/mongoose

Frequently Asked Questions

What is CVE-2025-51495? +

An integer overflow vulnerability exists in the WebSocket component of Mongoose 7.5 thru 7.17. By sending a specially crafted WebSocket request, an attacker can cause the application to crash. If downstream vendors integrate this component improperly, the issue may lead to a buffer overflow. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2025-51495? +

CVE-2025-51495 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2025-51495? +

CVE-2025-51495 affects products from cesanta, specifically: mongoose. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-51495? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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