Skip to content
Fencer Vulns
medium 5.4

CVE-2026-45692 json

Caddy: Remote Admin Authorization Bypass in `/config` API via Array Index Normalization

published 2026-05-19 5 mo ago modified 2026-10-25 14 d ago also GHSA-x5w9-xh9r-mvfc , GO-2026-5743 , EUVD-2026-38559

cvss
5.4
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 15%
public exploits
0
none known

Summary

Caddy is an extensible server platform that uses TLS by default. From 2.4.0 until 2.11.3, the authorization layer and the /config traversal layer do not agree on what object the path refers to. In this case, a path authorized for one config object is accepted, but then resolves to a different config object during traversal. This happens because the authorization layer uses string prefix matching and the /config traversal layer parses array indices numerically using strconv.Atoi(). This vulnerability is fixed in 2.11.3.

Patch / fix

  • go github.com/caddyserver/caddy/v2 2.11.3
  • caddyserver caddy 2.11.3
  • caddy Debian 12 2.6.2-5+deb12u1
  • caddy Debian 13 2.6.2-12+deb13u1
  • caddy Debian 14 2.11.4-1

debian advisories DEBIAN-CVE-2026-45692

  • govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1

opensuse advisories openSUSE-SU-2026:21483-1

  • caddy Alpine 3.24, Alpine 3.23 2.11.4-r0

alpine advisories ALPINE-CVE-2026-45692

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-45692 updated cvss 3.8

github.com/caddyserver/caddy/v2: Caddy: Remote Admin Authorization Bypass in `/config` API via Array Index Normalization

  • Red Hat Hardened Images caddy
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
4 mo ago

Exploit prediction

0.24% chance of exploitation in the next 30 days, higher than 15% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/caddyserver/caddy/security/advisories/GHSA-x5w9-xh9r-mvfc referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
NVD 3.1 3.8 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N
GitHub 3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

Affected packages

ecosystem package affected fixed in
go github.com/caddyserver/caddy/v2
>=2.4.0, <2.11.3
2.11.3

Affected products

  • caddyserver caddy

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.