CVE-2025-12543
unknown
CVSS v3
—
CVSS v2
—
VIR risk
—
Description
Undertow HTTP server core doesn't properly validate the Host header in incoming HTTP requests
Predictions
Exploit likelihood
30%
Patch ETA
—
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2025-12543
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| debian | forky | affected | |
| debian | sid | affected | |
Package impact
| Ecosystem | Package | Vulnerable | Fixed |
|---|---|---|---|
| Maven | io.undertow:undertow-core | | |
| Maven | io.undertow:undertow-core | >=2.3.0.Alpha1,<2.3.21.Final | 2.3.21.Final |
| Maven | io.undertow:undertow-core | <2.2.39.Final | 2.2.39.Final |
References
- https://nvd.nist.gov/vuln/detail/CVE-2025-12543
- https://github.com/undertow-io/undertow/pull/1860
- https://github.com/undertow-io/undertow/pull/1857
- https://issues.redhat.com/browse/UNDERTOW-2656
- https://github.com/undertow-io/undertow/releases/tag/2.3.21.Final
- https://github.com/undertow-io/undertow/releases/tag/2.2.39.Final
- https://github.com/undertow-io/undertow
- https://bugzilla.redhat.com/show_bug.cgi?id=2408784
- https://access.redhat.com/security/cve/CVE-2025-12543
- https://access.redhat.com/errata/RHSA-2026:4924
- https://access.redhat.com/errata/RHSA-2026:4917
- https://access.redhat.com/errata/RHSA-2026:4916
- https://access.redhat.com/errata/RHSA-2026:4915
- https://access.redhat.com/errata/RHSA-2026:3892
- https://access.redhat.com/errata/RHSA-2026:3891
- https://access.redhat.com/errata/RHSA-2026:3890
- https://access.redhat.com/errata/RHSA-2026:3889
- https://access.redhat.com/errata/RHSA-2026:0386
- https://access.redhat.com/errata/RHSA-2026:0384
- https://access.redhat.com/errata/RHSA-2026:0383
- https://security-tracker.debian.org/tracker/CVE-2025-12543
Verify integrity in audit chain (admin only). AS-IS.