5.3

CVE-2026-27860: dovecot LDAP Injection

CVSS: 5.3v3.1MediumAnalyzed
AliasesALPINE-CVE-2026-27860UBUNTU-CVE-2026-27860DEBIAN-CVE-2026-27860
Published 27-03-2026Last modified 27-03-2026
Open JSON

Vulnerability summary

CVE-2026-27860 is a medium (CVSS 5.3) LDAP Injection vulnerability in dovecot. EPSS estimates a 0.34% chance of exploitation in the next 30 days, higher than 26.3% of scored vulnerabilities.

Overall risk
21/100
0100
Low · default modelHow is this calculated?
CVSS score
5.3/10
010
Medium · v3.1 (NVD)
EPSS score
0.34%
0%100%
Low · +0.06 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 3 · Related 4
OPENSUSE-SU-2026:10442-1OPENSUSE-SU-2026:20554-1SUSE-SU-2026:21208-1USN-8136-1

Timeline

  1. 27-03-2026
    PublishedVulnerability first disclosed.
  2. 27-03-2026
    Last modifiedVulnerability information updated.

Description

If auth_username_chars is empty, it is possible to inject arbitrary LDAP filter to Dovecot's LDAP authentication. This leads to potentially bypassing restrictions and allows probing of LDAP structure. Do not clear out auth_username_chars, or install fixed version. No publicly available exploits are known.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

0.34%

Chance of exploitation in the next 30 days

Percentile

26%

Versus all other CVEs

30-day change

+0.06 pp

From 0.29% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.34%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Alpine1 product
  • dovecot< 2.4.3-r0
Debian1 product
  • dovecot< 1:2.4.1+dfsg1-6+deb13u4 | < 1:2.4.3+dfsg1-1
Dovecot1 product
Open-xchange1 product
Open-xchange gmbh1 product
Ubuntu1 product
  • dovecot< 1:2.4.1+dfsg1-5ubuntu4.1

6 vendors · 6 products

References

6 links