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Vulnerability record · CVE-2025-55181 · published 2 December 2025

CVE-2025-55181: Facebook proxygen vulnerability

Facebook · Proxygen

Sending an HTTP request/response body with greater than 2^31 bytes triggers an infinite loop in proxygen::coro::HTTPQuicCoroSession which blocks the backing event loop and unconditionally appends data to a std::vector per-loop iteration. This issue leads to unbounded memory growth and eventually causes the process to run out of memory.

5.3 CVSS 3.1 Medium EPSS 0.29% · top 80.3% CWE-834 · CWE-834
5.3CVSS 3.1 base score
0.29%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

Description

Sending an HTTP request/response body with greater than 2^31 bytes triggers an infinite loop in proxygen::coro::HTTPQuicCoroSession which blocks the backing event loop and unconditionally appends data to a std::vector per-loop iteration. This issue leads to unbounded memory growth and eventually causes the process to run out of memory.

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/facebook/proxygen/commit/17689399ef99b7c3d3a8b2b768b1dba1a4b72f8f Patch
https://www.facebook.com/security/advisories/cve-2025-55181 Vendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2025-55181), CISA KEV, FIRST EPSS (scores of 2026-09-29). This page is refreshed as NVD updates the record.