DEBIAN-CVE-2026-52845

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Source
https://security-tracker.debian.org/tracker/CVE-2026-52845
Import Source
https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-52845.json
JSON Data
https://api.osv.dev/v1/vulns/DEBIAN-CVE-2026-52845
Upstream
Published
2026-06-23T18:18:05.267Z
Modified
2026-06-25T23:00:32.185974802Z
Severity
  • 8.1 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N CVSS Calculator
Summary
[none]
Details

Caddy is an extensible server platform that uses TLS by default. Prior to 2.11.4, forwardauth copyheaders deletes the exact client-supplied identity header before copying the trusted value from the auth gateway. But when the request later goes through php_fastcgi, Caddy normalizes HTTP headers into CGI variables by replacing - with . This lets a client send an underscore alias that survives the forwardauth delete step but becomes the same PHP/FastCGI variable. Result: a remote client can inject or sometimes override identity/group headers trusted by PHP/FastCGI applications behind Caddy. This vulnerability is fixed in 2.11.4.

References

Affected packages

Debian:12 / caddy

Package

Name
caddy
Purl
pkg:deb/debian/caddy?arch=source&distro=bookworm

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.6.2-5
2.6.2-6
2.6.2-6.1
2.6.2-7
2.6.2-8
2.6.2-9
2.6.2-10
2.6.2-11
2.6.2-12
2.6.2-13
2.6.2-14
2.11.2-1~bpo13+1
2.11.2-1

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-52845.json"

Debian:13 / caddy

Package

Name
caddy
Purl
pkg:deb/debian/caddy?arch=source&distro=trixie

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.6.2-12
2.6.2-13
2.6.2-14
2.11.2-1~bpo13+1
2.11.2-1

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-52845.json"

Debian:14 / caddy

Package

Name
caddy
Purl
pkg:deb/debian/caddy?arch=source&distro=forky

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.6.2-12
2.6.2-13
2.6.2-14
2.11.2-1~bpo13+1
2.11.2-1

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-52845.json"