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Fencer Vulns
medium 6.8

CVE-2020-24386 json

An issue was discovered in Dovecot before 2.3.13.

published 2021-01-04 5 y ago modified 2026-06-17 4 mo ago also EUVD-2020-17118

cvss
6.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
2.8%
EPSS 2.8% chance of exploitation in 30 days, percentile 86%
public exploits
0
none known

Summary

An issue was discovered in Dovecot before 2.3.13. By using IMAP IDLE, an authenticated attacker can trigger unhibernation via attacker-controlled parameters, leading to access to other users' email messages (and path disclosure).

Patch / fix

  • dovecot dovecot 2.3.13
  • dovecot Debian 14, Debian 13, Debian 12 1:2.3.13+dfsg1-1

debian advisories DEBIAN-CVE-2020-24386

  • dovecot Ubuntu 18.04 LTS 1:2.2.33.2-1ubuntu4.7
  • dovecot Ubuntu 20.04 LTS 1:2.3.7.2-1ubuntu3.3

ubuntu advisories UBUNTU-CVE-2020-24386

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • dovecot RHEL 8 1:2.3.8-9.el8
  • dovecot-mysql RHEL 8 1:2.3.8-9.el8
  • dovecot-pgsql RHEL 8 1:2.3.8-9.el8
  • dovecot-pigeonhole RHEL 8 1:2.3.8-9.el8

red hat advisories RHSA-2021:1887

  • dovecot23 SLES for SAP 15, SLES 15-LTSS, SLE High Performance Computing 15-LTSS +1 more 2.3.11.3-4.32.1
  • dovecot23 SLE Module for Server Applications 15 SP2 2.3.11.3-17.5.1
  • dovecot23 SLE Module for Server Applications 15 SP1 2.3.11.3-21.1
  • dovecot22 SLES for SAP 12 SP5, SLES for SAP 12 SP4, SLES for SAP 12 SP3 +15 more 2.2.31-19.25.1

suse advisories SUSE-SU-2021:0029-1SUSE-SU-2021:0028-1SUSE-SU-2021:0027-1SUSE-SU-2021:0018-1

  • dovecot24 openSUSE Tumbleweed 2.4.0-1.1
  • dovecot23 openSUSE Tumbleweed 2.3.16-1.6
  • dovecot23 openSUSE Leap 15.1 2.3.11.3-lp151.2.15.1
  • dovecot23 openSUSE Leap 15.2 2.3.11.3-lp152.2.6.1

opensuse advisories openSUSE-SU-2025:14715-1openSUSE-SU-2024:10726-1openSUSE-SU-2021:0072-1openSUSE-SU-2021:0026-1

  • dovecot AlmaLinux 8 1:2.3.8-9.el8
  • dovecot-mysql AlmaLinux 8 1:2.3.8-9.el8
  • dovecot-pgsql AlmaLinux 8 1:2.3.8-9.el8
  • dovecot-pigeonhole AlmaLinux 8 1:2.3.8-9.el8

almalinux advisories ALSA-2021:1887

  • dovecot Alpine 3.24, Alpine 3.23, Alpine 3.22 +12 more 2.3.13-r0

alpine advisories ALPINE-CVE-2020-24386

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • dovecot Arch Linux 2.3.13-1

arch linux advisories AVG-1398

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2020-24386 updated cvss 6.8

dovecot: IMAP hibernation function allows mail access

  • Red Hat Enterprise Linux 5 dovecot Red Hat Enterprise Linux 6 dovecot, dovecot-mysql, dovecot-pgsql, dovecot-pigeonhole Red Hat Enterprise Linux 7 dovecot, dovecot-mysql, dovecot-pgsql, dovecot-pigeonhole
    affected: workaround, no fix planned “To mitigate this flaw, ensure that imap_hibernate_timeout is set to 0 or not set at all/commented out in both /etc/dovecot/dovecot.conf or /etc/dovecot/conf.d/20-imap.conf.”
  • Red Hat Enterprise Linux 9 dovecot, dovecot-mysql, dovecot-pgsql, dovecot-pigeonhole
    affected: workaround, no fix available “To mitigate this flaw, ensure that imap_hibernate_timeout is set to 0 or not set at all/commented out in both /etc/dovecot/dovecot.conf or /etc/dovecot/conf.d/20-imap.conf.”
  • Red Hat CodeReady Linux Builder (v. 8) dovecot 2.3.8-9.el8 Red Hat Enterprise Linux AppStream (v. 8) dovecot 2.3.8-9.el8, dovecot-mysql 2.3.8-9.el8, dovecot-pgsql 2.3.8-9.el8, dovecot-pigeonhole 2.3.8-9.el8
    fixed: vendor fix “To mitigate this flaw, ensure that imap_hibernate_timeout is set to 0 or not set at all/commented out in both /etc/dovecot/dovecot.conf or /etc/dovecot/conf.d/20-imap.conf.” RHSA-2021:1887

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

2.78% chance of exploitation in the next 30 days, higher than 86% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 6.8 CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
NVD 2.0 4.9 AV:N/AC:M/Au:S/C:P/I:P/A:N

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.