CVE-2026-27858
Publication date 27 March 2026
Last updated 1 April 2026
Ubuntu priority
Description
Attacker can send a specifically crafted message before authentication that causes managesieve to allocate large amount of memory. Attacker can force managesieve-login to be unavailable by repeatedly crashing the process. Protect access to managesieve protocol, or install fixed version. No publicly available exploits are known.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| dovecot | 26.04 LTS resolute |
Not affected
|
| 25.10 questing |
Fixed 1:2.4.1+dfsg1-5ubuntu4.1
|
|
| 24.04 LTS noble |
Fixed 1:2.3.21+dfsg1-2ubuntu6.3
|
|
| 22.04 LTS jammy |
Fixed 1:2.3.16+dfsg1-3ubuntu2.7
|
|
| 20.04 LTS focal |
Vulnerable
|
|
| 18.04 LTS bionic |
Vulnerable
|
|
| 16.04 LTS xenial |
Vulnerable
|
|
| 14.04 LTS trusty |
Vulnerable
|
Severity score breakdown
CVSS version: CVSS v3.0
Base score
7.5 · High
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
Related Ubuntu Security Notices (USN)
- USN-8136-1
- Dovecot vulnerabilities
- 31 March 2026