CVE-2026-40020

Publication date 12 May 2026

Last updated 5 June 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

3.1 · Low

Score breakdown

Description

Attacker can use the IMAP SETACL command to inject the anyone permission to user's dovecot-acl file even if imap_acl_allow_anyone=no. This causes folders to be spammed to all users. The impact is limited to being able to spam folders to other users, no unexpected access is gained. Install to fixed version. No publicly available exploits are known.

Status

Package Ubuntu Release Status
dovecot 26.04 LTS resolute
Fixed 1:2.4.2+dfsg1-3ubuntu2.1
25.10 questing
Fixed 1:2.4.1+dfsg1-5ubuntu4.2
24.04 LTS noble
Fixed 1:2.3.21+dfsg1-2ubuntu6.5
22.04 LTS jammy
Fixed 1:2.3.16+dfsg1-3ubuntu2.9
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
14.04 LTS trusty
Needs evaluation

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
dovecot

Severity score breakdown

CVSS version: CVSS v3.0

Base score 3.1 · Low

Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L

References

Related Ubuntu Security Notices (USN)

Other references

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