What is CVE-2026-31870?

CVE-2026-31870 is a high-severity vulnerability in Yhirose Cpp-httplib, classified under CWE-248. CVSS score: 7.5/10. Published 2026-03-11.

How severe is CVE-2026-31870?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in Yhirose Cpp-httplib

CVE-2026-31870

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.37.1, when a cpp-httplib client uses the streaming API (httplib::stream::Get, httplib::stream::Post, etc.), the library calls std::stoull() direct…

EPSS: 0.001 (30.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Yhirose Cpp-httplib — versions < 0.37.1

Weakness classification (CWE)

CWE-248

References

https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-39q5-hh6x-jpxx (x_refsource_CONFIRM)

Frequently asked questions

What is CVE-2026-31870?: CVE-2026-31870 is a high-severity vulnerability in Yhirose Cpp-httplib, classified under CWE-248. CVSS score: 7.5/10. Published 2026-03-11.
How severe is CVE-2026-31870?: High severity. CVSS v3 base score is 7.5 out of 10.