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CVE-2026-42006

4.3 MEDIUM

An attacker can cause uncontrolled memory usage with excessive bracing over IMAP

Published: 2026-05-12 · Last updated: 2026-05-18

Severity and scoring

CVSS
4.3 MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
CWE
CWE-400

Affected products

VendorProduct
dovecotdovecot
open-xchangedovecot

Description

An attacker can cause uncontrolled memory usage with excessive bracing over IMAP. The fix in CVE-2026-27857 was incomplete, only blocking one way of doing this, so there was still another way left open. In particular, the fix was for closing braces, but you could still use open braces to bypass the limit. Using excessive bracing, attacker can cause memory usage up to configured memory limit. Install fixed version, or configure vsz_limit for imap process to low value. No publicly available exploits are known.

Source: NVD

References

Related CVEs

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