Description
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. In version 0.21.0, when many http headers fields are passed in, the library does not limit the number of headers, and the memory associated with the headers will not be released when the connection is disconnected. This leads to potential exhaustion of system memory and results in a server crash or unresponsiveness. Version 0.22.0 contains a patch for the issue.
References (2)
Core 2
Core References
Exploit, Vendor Advisory x_refsource_confirm
https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-xjhg-gf59-p92h
Scores
CVSS v3
7.5
EPSS
0.0054
EPSS Percentile
67.8%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-400
Status
published
Products (1)
yhirose/cpp-httplib
0.21.0
Published
Jun 26, 2025
Tracked Since
Feb 18, 2026