CVE catalog

CVE-2026-77341

cpp-httplib is a C++ header-only HTTP/HTTPS library. In version 0.49.0, the chunked-response trailer output path writes trailer header names and values directly to the socket without validating them,

[CVE catalog]

Severity: Medium · CVSS 5.3CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Published: Aug 27, 2026, 10:16:45 PM UTC
Updated: Aug 28, 2026, 12:18:15 AM UTC
Source: [NVD] · [CVE record]
EPSS: 0.46% · Oct 25, 2026

cpp-httplib is a C++ header-only HTTP/HTTPS library. In version 0.49.0, the chunked-response trailer output path writes trailer header names and values directly to the socket without validating them, allowing CRLF sequences in a trailer field to inject additional headers or split the HTTP response. Unlike every other header-writing path in the library, the trailer-writing code applies none of the field-name and field-value checks that reject carriage return and line feed, so an application that places attacker-influenced data into a chunked response trailer emits attacker-controlled CRLF onto the wire. This enables HTTP response splitting, letting an attacker forge response headers or inject a second response. This issue is fixed in version 0.50.0.

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`	vulnerable
Debian	cpp-httplib	forky	`0.41.0+ds-3`	vulnerable
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
Opensuse	ccache	tumbleweed	`4.14.1-1.1`	fixed

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	cpp-httplib	source	sid	`(unfixed)`	not yet assigned	Not reported	[1145976]
Debian	cpp-httplib	source	forky	`(unfixed)`	not yet assigned	Not reported	[1145976]
Debian	cpp-httplib	source	trixie	`(unfixed)`	not yet assigned	Not reported	[1145976]
Debian	cpp-httplib	source	bookworm	`(unfixed)`	not yet assigned	Not reported	[1145976]
Opensuse	ccache	rpm	tumbleweed	`4.14.1-1.1`	Not reported	OPENSUSE-SU-2026:11979-1	Not reported

[Debian bug #1145976]

Notes

[trixie] cpp-httplib: Minor issue [bookworm] cpp-httplib: Minor issue

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
  nvd · cpp-httplib · debian · bookworm; nvd · cpp-httplib · debian · 12
- 0.11.4+ds-1+deb12u1 · arm64 · bookworm
  Affected
  nvd · cpp-httplib · debian · bookworm; nvd · cpp-httplib · debian · 12
[libcpp-httplib-dev]Affected
Source package: [cpp-httplib]
Details (2)
- 0.11.4+ds-1+deb12u1 · amd64 · bookworm
  Affected
  nvd · cpp-httplib · debian · bookworm; nvd · cpp-httplib · debian · 12
- 0.11.4+ds-1+deb12u1 · arm64 · bookworm
  Affected
  nvd · cpp-httplib · debian · bookworm; nvd · 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
  nvd · cpp-httplib · debian · 13
- 0.18.7-1+deb13u1 · arm64 · trixie
  Affected
  nvd · cpp-httplib · debian · 13
- 0.18.7-1+deb13u1 · amd64 · trixie-security
  Affected
  nvd · cpp-httplib · debian · 13
- 0.18.7-1+deb13u1 · arm64 · trixie-security
  Affected
  nvd · 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
  nvd · cpp-httplib · debian · 13
- 0.41.0+ds-3~bpo13+1 · arm64 · trixie-backports
  Affected
  nvd · cpp-httplib · debian · 13
[libcpp-httplib-dev]Affected
Source package: [cpp-httplib]
Details (6)
- 0.18.7-1+deb13u1 · amd64 · trixie
  Affected
  nvd · cpp-httplib · debian · 13
- 0.18.7-1+deb13u1 · arm64 · trixie
  Affected
  nvd · cpp-httplib · debian · 13
- 0.41.0+ds-3~bpo13+1 · amd64 · trixie-backports
  Affected
  nvd · cpp-httplib · debian · 13
- 0.41.0+ds-3~bpo13+1 · arm64 · trixie-backports
  Affected
  nvd · cpp-httplib · debian · 13
- 0.18.7-1+deb13u1 · amd64 · trixie-security
  Affected
  nvd · cpp-httplib · debian · 13
- 0.18.7-1+deb13u1 · arm64 · trixie-security
  Affected
  nvd · cpp-httplib · debian · 13

[openSUSE Tumbleweed]

[ccache]Affected
Source package: [ccache]
Details (1)
- 4.14-1.1 · x86_64 · tumbleweed
  Affected · Fixed: 4.14.1-1.1
  nvd · ccache · opensuse · tumbleweed

Observed: Oct 27, 2026, 6:57:25 AM UTC

References

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