Information disclosure in Yhirose Cpp-Httplib
CVE-2026-33745
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.39.0, the cpp-httplib HTTP client forwards stored Basic Auth, Bearer Token, and Digest Auth credentials to arbitrary hosts when following cross-origin HTTP redirects (301/302/307/308). A malicious or compromised server can redirect the client to an attacker-controlled host, which then receives the plaintext credentials in the `Authorization` header. Version 0.39.0 fixes the issue.
Vulnerability class: Information Disclosure
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.004 (27.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 27.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001
Affected products
- Yhirose Cpp-Httplib — versions < 0.39.0
Weakness classification (CWE)
References
- github.com/yhirose/cpp-httplib/security/advisories/GHSA-6hrp-7fq9-3qv2 (Exploit, Mitigation, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-33745?
- CVE-2026-33745 is a high-severity vulnerability in Yhirose Cpp-Httplib, classified under Information Disclosure. CVSS score: 7.4/10. Published 2026-03-27.
- How severe is CVE-2026-33745?
- High severity. CVSS v3 base score is 7.4 out of 10.