CVE-2026-40204: open-xchange gmbh ox dovecot ce Improper Access Control
CVSS: 3.1v3.1LowDeferred
AliasesUBUNTU-CVE-2026-40204DEBIAN-CVE-2026-40204
Published 28-08-2026Last modified 28-08-2026
Vulnerability summary
CVE-2026-40204 is a low (CVSS 3.1) Improper Access Control vulnerability in open-xchange gmbh ox dovecot ce. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 10.7% of scored vulnerabilities.
CVSS score
3.1/10
010
Low · v3.1 (CVE.org)EPSS score
0.21%
0%100%
Low · +0.03 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 3 · Related 2Timeline
- 28-08-2026PublishedVulnerability first disclosed.
- 28-08-2026Last modifiedVulnerability information updated.
Description
None None None No publicly available exploits are known.
CVSS metrics
4 scores · 4 sources · 1 versionLow 3.1Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:NSourcesAll 4 agree
- OSV · UbuntuEcosystem advisory · calculated3.1LowCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
- OSV · DebianEcosystem advisory · calculated3.1LowCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
- NVDNIST3.1LowCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
EPSS trend
Probability
0.21%
Chance of exploitation in the next 30 days
Percentile
11%
Versus all other CVEs
30-day change
+0.03 pp
From 0.18% on 21-09-2026
21-09-202621-10-2026
EPSS score0.21%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Open-xchange gmbh2 products
- ox dovecot ce≥ 2.3.0, < 2.4.5
- ox dovecot pro≥ 2.3.0, < 2.3.22.2 | ≥ 3.0.0, < 3.0.7 | ≥ 3.1.0, < 3.1.6
Debian1 product
- dovecotAll versions (No fix recorded) | < 1:2.4.1+dfsg1-6+deb13u7 | < 1:2.4.5+dfsg1-1
Ubuntu1 product
- dovecotAll versions (No fix recorded)
3 vendors · 4 products
