CVE catalog

CVE-2025-66577

cpp-httplib: CVE-2025-66577

Severity: Medium · CVSS 5.3CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Published: Dec 5, 2025, 6:20:25 PM UTC
Source: [NVD] · [CVE record]
EPSS: 0.27% · Oct 25, 2026

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.27.0, a vulnerability allows attacker-controlled HTTP headers to influence server-visible metadata, logging, and authorization decisions. An attacker can supply X-Forwarded-For or X-Real-IP headers which get accepted unconditionally by get_client_ip() in docker/main.cc, causing access and error logs (nginx_access_logger / nginx_error_logger) to record spoofed client IPs (log poisoning / audit evasion). This vulnerability is fixed in 0.27.0.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	cpp-httplib	sid	`0.41.0+ds-3`	fixed
Debian	cpp-httplib	forky	`0.41.0+ds-3`	fixed
Debian	cpp-httplib	trixie	`0.18.7-1+deb13u1`	vulnerable
Debian	cpp-httplib	trixie-security	`0.18.7-1+deb13u1`	vulnerable
Debian	cpp-httplib	bookworm	`0.11.4+ds-1+deb12u1`	vulnerable

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	cpp-httplib	source	sid	`0.41.0+ds-3`	not yet assigned	Not reported	[1122027]
Debian	cpp-httplib	source	forky	`0.41.0+ds-3`	not yet assigned	Not reported	[1122027]
Debian	cpp-httplib	source	trixie	`(unfixed)`	not yet assigned	Not reported	[1122027]
Debian	cpp-httplib	source	bookworm	`(unfixed)`	not yet assigned	Not reported	[1122027]

[Debian bug #1122027]

OpenFactory catalog packages

[Debian 12 (Bookworm)]

[libcpp-httplib0.11]Affected
Source package: [cpp-httplib]
Details (2)
- 0.11.4+ds-1+deb12u1 · amd64 · bookworm
  Affected
  dsa · cpp-httplib · debian · bookworm; dsa · cpp-httplib · debian · 12
- 0.11.4+ds-1+deb12u1 · arm64 · bookworm
  Affected
  dsa · cpp-httplib · debian · bookworm; dsa · cpp-httplib · debian · 12
[libcpp-httplib-dev]Affected
Source package: [cpp-httplib]
Details (2)
- 0.11.4+ds-1+deb12u1 · amd64 · bookworm
  Affected
  dsa · cpp-httplib · debian · bookworm; dsa · cpp-httplib · debian · 12
- 0.11.4+ds-1+deb12u1 · arm64 · bookworm
  Affected
  dsa · cpp-httplib · debian · bookworm; dsa · cpp-httplib · debian · 12

[Debian 13 (Trixie)]

[libcpp-httplib0.18]Affected
Source package: [cpp-httplib]
Details (4)
- 0.18.7-1+deb13u1 · amd64 · trixie
  Affected
  dsa · cpp-httplib · debian · 13
- 0.18.7-1+deb13u1 · arm64 · trixie
  Affected
  dsa · cpp-httplib · debian · 13
- 0.18.7-1+deb13u1 · amd64 · trixie-security
  Affected
  dsa · cpp-httplib · debian · 13
- 0.18.7-1+deb13u1 · arm64 · trixie-security
  Affected
  dsa · cpp-httplib · debian · 13
[libcpp-httplib0.41]Affected
Source package: [cpp-httplib]
Details (2)
- 0.41.0+ds-3~bpo13+1 · amd64 · trixie-backports
  Affected
  dsa · cpp-httplib · debian · 13
- 0.41.0+ds-3~bpo13+1 · arm64 · trixie-backports
  Affected
  dsa · cpp-httplib · debian · 13
[libcpp-httplib-dev]Affected
Source package: [cpp-httplib]
Details (6)
- 0.18.7-1+deb13u1 · amd64 · trixie
  Affected
  dsa · cpp-httplib · debian · 13
- 0.18.7-1+deb13u1 · arm64 · trixie
  Affected
  dsa · cpp-httplib · debian · 13
- 0.41.0+ds-3~bpo13+1 · amd64 · trixie-backports
  Affected
  dsa · cpp-httplib · debian · 13
- 0.41.0+ds-3~bpo13+1 · arm64 · trixie-backports
  Affected
  dsa · cpp-httplib · debian · 13
- 0.18.7-1+deb13u1 · amd64 · trixie-security
  Affected
  dsa · cpp-httplib · debian · 13
- 0.18.7-1+deb13u1 · arm64 · trixie-security
  Affected
  dsa · cpp-httplib · debian · 13

Observed: Oct 27, 2026, 10:56:04 AM UTC

References

[Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]