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4.3Medium

CVE-2026-42006

Open-Xchange GmbH OX Dovecot Pro; Red Hat Red Hat Enterprise Linux 10; Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support; Red Hat Red Hat Enterpris… Published: (6 months ago)

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.

Weakness (CWE): CWE-400CWE-770

Data: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Published as the sources state it, in English.

Affected products and versions

VendorProductVersions
dovecot dovecot < 2.4.4
open-xchange dovecot < 3.1.5
Open-Xchange GmbH OX Dovecot Pro ≤ 3.0.5, ≤ 3.1.4, ≤ 2.4.3
Red Hat Red Hat Enterprise Linux 10 all versions
Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support all versions
Red Hat Red Hat Enterprise Linux 6 —
Red Hat Red Hat Enterprise Linux 7 Extended Lifecycle Support all versions
Red Hat Red Hat Enterprise Linux 8 all versions
Red Hat Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support all versions
Red Hat Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On all versions
Red Hat Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support all versions
Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On all versions
Red Hat Red Hat Enterprise Linux 8.8 Telecommunications Update Service all versions
Red Hat Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions all versions
Red Hat Red Hat Enterprise Linux 9 all versions
Red Hat Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions all versions
Red Hat Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions all versions
Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support all versions

References and patches

CPE matches (NVD) (2)
  • cpe:2.3:a:dovecot:dovecot:*:*:*:*:*:*:*:* < 2.4.4
  • cpe:2.3:a:open-xchange:dovecot:*:*:*:*:pro:*:*:* < 3.1.5

Recent CVEs in the same product — Dovecot

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5.3Medium
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