CVE-2026-45372
Last modified
CVE-2026-45372 is a critical-severity vulnerability rated 9.9/10 on the CVSS scale. cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.44.0, when cpp-httplib's server parses an incoming request, it applies percent-decoding to every header value except Location and Referer. EPSS estimates a 0.29% chance of exploitation in the next 30 days.
Description
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.44.0, when cpp-httplib's server parses an incoming request, it applies percent-decoding to every header value except Location and Referer. The validity check (is_field_value) is run before decoding, so encoded %0D%0A passes the check and is then expanded to a literal \r\n byte pair inside the stored header value. This vulnerability is fixed in 0.44.0.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:L
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Yhirose | Cpp-Httplib | < 0.44.0 |
References
- https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-xjxg-64p4-vj4mExploit, Mitigation, Vendor Advisory
- https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-xjxg-64p4-vj4mExploit, Mitigation, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
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