What’s Vulnerable › Vulnerabilities

CVE-2026-22776: cpp-httplib vulnerable to a denial of service (DOS) using a zip bomb

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-01-12 · updated 2026-06-17
• Weakness: CWE-409

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.

Affected products

• yhirose cpp-httplib: before 0.30.1 — fixed in 0.30.1

How to fix

Upgrade to a fixed version: yhirose cpp-httplib 0.30.1. Check the vendor advisory for mitigations.

References

• https://github.com/yhirose/cpp-httplib/commit/2e2e47bab1ae6a853476eecbc4bf279dd1fef792
• https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-h934-98h4-j43q

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