CVE-2026-27856
CVE-2026-27856 Vulnerability Analysis & Exploit Intelligence
Doveadm credentials are verified using direct comparison which is susceptible to timing oracle attack. An attacker can use this to determine the configured credentials. Figuring out the credential will lead into full access to the affected component. Limit access to the doveadm http service port, install fixed version. No publicly available exploits are known.
Published Updated Sources: cvelistV5, OX
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Unreported
no source claims exploitation
EPSS
0%
chance of exploitation in 30 days
CVSS base
7.4
HIGH
CISA SSVC assessment
Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.
Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script all four kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component
Affected scope
The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.
Vendors (2)
Products (6)
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 7.4 | CVSS 3.1 | HIGH | — | — | cvelistV5 |
Weakness & attack patterns
- CWE-287
- CWE-208
Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.
- T1548Abuse Elevation Control Mechanism
- T1040Network Sniffing
- T1185Browser Session Hijacking
References
5 on the record
- documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0001.json
vendor-advisory
- access.redhat.com/security/cve/CVE-2026-27856
vdb-entry, x_refsource_REDHAT
- bugzilla.redhat.com/show_bug.cgi?id=2452171
issue-tracking, x_refsource_REDHAT
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27856.json
x_sadp-csaf-vex
- access.redhat.com/errata/RHSA-2026:26564
vendor-advisory, x_refsource_REDHAT
Elsewhere on this site
- open xchangeevery CVE for this vendor
- redhatevery CVE for this vendor
- CWE-287other pages naming this weakness
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.