High severity · published Jan 12, 2026
CVE-2026-22776
cpp-httplib vulnerable to a denial of service (DOS) using a zip bomb
7.5
CVSS
0.4%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 35% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CP
cpp-httplib · yhirose
< 0.30.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-22776
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-22776
Patch
https://github.com/yhirose/cpp-httplib/commit/2e2e47bab1ae6a853476eecbc4bf279dd1fef792
Exploit
https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-h934-98h4-j43q
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