HTTP Request Smuggling Affecting cpp-httplib package, versions <0.18.7-1+e3


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
0.52% (43rd percentile)

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  • Snyk IDSNYK-ECHOLATEST-CPPHTTPLIB-19401928
  • published28 Aug 2026
  • disclosed10 Jul 2025

Introduced: 10 Jul 2025

CVE-2025-53628  (opens in a new tab)
CWE-444  (opens in a new tab)

How to fix?

Upgrade Echo:latest cpp-httplib to version 0.18.7-1+e3 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream cpp-httplib package and not the cpp-httplib package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.20.1, cpp-httplib does not have a limit for a unique line, permitting an attacker to explore this to allocate memory arbitrarily. This vulnerability is fixed in 0.20.1. NOTE: This vulnerability is related to CVE-2025-53629.

CVSS Base Scores

version 3.1