| Name | CVE-2026-42008 |
| Description | Forwarding information received from a host listed as a trusted proxy is not kept separate from Dovecot's own authentication fields, so a value sent by that host can be injected as an internal authentication field. Any host permitted to act as a trusted proxy can authenticate as any user without knowing that user's password. This affects deployments whose password database honours a field that permits authentication without a password. Deployments that do not configure trusted proxies are not affected. Restrict the list of trusted proxy networks to hosts that are fully under your control. Update to non-vulnerable version. No publicly available exploits are known. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| References | DLA-4873-1, DSA-6526-1 |
| Debian Bugs | 1146018 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| dovecot (PTS) | bookworm | 1:2.3.19.1+dfsg1-2.1+deb12u6 | vulnerable |
| bookworm (security) | 1:2.3.19.1+dfsg1-2.1+deb12u7 | fixed | |
| trixie | 1:2.4.1+dfsg1-6+deb13u6 | vulnerable | |
| trixie (security) | 1:2.4.1+dfsg1-6+deb13u7 | fixed | |
| forky, sid | 1:2.4.5+dfsg1-4 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| dovecot | source | bookworm | 1:2.3.19.1+dfsg1-2.1+deb12u7 | DLA-4873-1 | ||
| dovecot | source | trixie | 1:2.4.1+dfsg1-6+deb13u7 | DSA-6526-1 | ||
| dovecot | source | (unstable) | 1:2.4.5+dfsg1-1 | 1146018 |
https://documentation.open-xchange.com/dovecot/security/advisories/html/2026/oxdc-adv-2026-0003.html#cve-2026-42008-xclient-forward-bare-token-not-namespaced-allows-nopassword-injection-via-trusted-proxy
Fixed by: https://github.com/dovecot/core/commit/da832e63e91d640e9a4bc57189c488cd97d99477
Fixed by: https://github.com/dovecot/core/commit/bc04ca866cbdd9a3228816fbc302c2024d207995
Fixed by: https://github.com/dovecot/core/commit/335abc77650a69860ff522ba87e714173a4e6049
Fixed by: https://github.com/dovecot/core/commit/7e60077cafabc3626a6bd7071b753e1c57415558