CVE-2026-22776

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.30.1, a Denial of Service (DoS) vulnerability exists in cpp-httplib due to the unsafe handling of compressed HTTP request bodies (Content-Encoding: gzip, br, etc.). The library validates the payload_max_length against the compressed data size received from the network, but does not limit the size of the decompressed data stored in memory.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/yhirose/cpp-httplib/commit/2e2e47bab1ae6a853476eecbc4bf279dd1fef792	Patch
https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-h934-98h4-j43q	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:yhirose:cpp-httplib:*:*:*:*:*:*:*:*

History

15 Jan 2026, 22:43

Type	Values Removed	Values Added
References	~~() https://github.com/yhirose/cpp-httplib/commit/2e2e47bab1ae6a853476eecbc4bf279dd1fef792 -~~	() https://github.com/yhirose/cpp-httplib/commit/2e2e47bab1ae6a853476eecbc4bf279dd1fef792 - Patch
References	~~() https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-h934-98h4-j43q -~~	() https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-h934-98h4-j43q - Exploit, Vendor Advisory
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
CPE		cpe:2.3:a:yhirose:cpp-httplib::::::::
First Time		Yhirose cpp-httplib Yhirose

12 Jan 2026, 19:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-12 19:16

Updated : 2026-01-15 22:43

NVD link : CVE-2026-22776

Mitre link : CVE-2026-22776

CVE.ORG link : CVE-2026-22776

JSON object : View

Products Affected

yhirose

cpp-httplib

CWE

CWE-409

Improper Handling of Highly Compressed Data (Data Amplification)

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