# CVE-2026-22776: cpp-httplib: cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library

CVE-2026-22776 is fixed in cpp-httplib on 1 platform by DEBIAN-CVE-2026-22776 (version 0.41.0+ds-3), released January 12, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-22776
- Priority: High
- CVSS: 7.5 (high)
- EPSS: 0.0041
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jan 12, 2026

## 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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | cpp-httplib Debian 14 | 0.41.0+ds-3 | [DEBIAN-CVE-2026-22776](https://patchblox.com/security/data/fix/linux/debian-cve-2026-22776.md) | Jan 12, 2026 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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