Vulnerability · Published Jun 26, 2025 · Assigned by GitHub_M

CVE-2025-52887cpp-httplib has unlimited number of http header fields, which causes memory leak

High 7.5

In plain English

A high-severity uncontrolled resource consumption in cpp-httplib from yhirose. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.5%top 57.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. In version 0.21.0, when many http headers fields are passed in, the library does not limit the number of headers, and the memory associated with the headers will not be released when the connection is disconnected. This leads to potential exhaustion of system memory and results in a server crash or unresponsiveness. Version 0.22.0 contains a patch for the issue.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Ubuntu:25.10cpp-httplibno fix listedUBUNTU-CVE-2025-52887

Affected products (as reported)

VendorProductVersions
yhirose cpp-httplib = 0.21.0

Weakness: CWE-400 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References