CriticalFix available
cpp-httplib — security advisory
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.
- Products
- cpp-httplib
- Affected versions
- 0.10.1+ds-1, 0.10.2+ds-1, 0.10.3+ds-1, 0.10.3+ds-1ubuntu0.1~esm1, 0.13.1+ds-1ubuntu1, 0.14.3+ds-1, 0.14.3+ds-1.1, 0.14.3+ds-1.1build1, 0.14.3+ds-1.1build2, 0.14.3+ds-1.1ubuntu0.1~esm1, 0.18.7-1, 0.18.7-1ubuntu0.25.10.1, 0.26.0+ds-2ubuntu2, 0.26.0+ds-2ubuntu3, 0.26.0+ds-2ubuntu4, 0.9.10+ds-1, 0.9.9+ds-1
- Fixed versions
- 0.10.3+ds-1ubuntu0.1~esm2, 0.14.3+ds-1.1ubuntu0.1~esm2, 0.18.7-1ubuntu0.25.10.2, 0.26.0+ds-2ubuntu3+esm1
- CVEs
- CVE-2026-45372
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 02:14 UTC · Revision 1
Source evidence
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.
osv:UBUNTU-CVE-2026-45372
cpp-httplib
Fixed versions: 0.10.3+ds-1ubuntu0.1~esm2
cpp-httplib
Fixed versions: 0.14.3+ds-1.1ubuntu0.1~esm2
cpp-httplib
Fixed versions: 0.18.7-1ubuntu0.25.10.2
cpp-httplib
Fixed versions: Not specified
cpp-httplib
Fixed versions: 0.26.0+ds-2ubuntu3+esm1
Complete source record
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