Description
cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.30.0, the ``write_headers`` function does not check for CR & LF characters in user supplied headers, allowing untrusted header value to escape header lines.
This vulnerability allows attackers to add extra headers, modify request body unexpectedly & trigger an SSRF attack. When combined with a server that supports http1.1 pipelining (springboot, python twisted etc), this can be used for server side request forgery (SSRF). Version 0.30.0 fixes this issue.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| yhirose | cpp-httplib | < 0.30.0 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | cpp-httplib | 0.41.0+ds-3 | — |
| Debian 13 | cpp-httplib | No fix yet | — |
| Debian 12 | cpp-httplib | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | cpp-httplib | No fix yet | — |
| Ubuntu 25.10 | cpp-httplib | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 26.04 LTS | cpp-httplib | No fix yet | — |
| Ubuntu Pro 24.04 LTS | cpp-httplib | No fix yet | — |
| Ubuntu Pro 22.04 LTS | cpp-httplib | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | cpp-httplib | 0.38.0-1.1 | openSUSE-SU-2026:10435-1 |
Advisories 1
- openSUSE-SU-2026:10435-1 cpp-httplib-devel-0.38.0-1.1 on GA media SUSE / openSUSE Security Updates · Mar 27, 2026