The IMAP and LMTP components in Dovecot 2.3.9 before 2.3.9.3 mishandle snippet generation…
Priority LOW 28CWE-20Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · Low
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA.
Summary
The IMAP and LMTP components in Dovecot 2.3.9 before 2.3.9.3 mishandle snippet generation when many characters must be read to compute the snippet and a trailing > character exists. This causes a denial of service in which the recipient cannot read all of their messages.
Why it matters now
EPSS 0.01877 79th percentileScored 2026-11-07
Public exploit Yes 2 exploit referencesTagged by NVD
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 3
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:dovecot:dovecot:*:*:*:*:*:*:*:* | 2.3.9 to before 2.3.9.3 | Vulnerable | The Dovecot Project |
| cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:* | 30 | Vulnerable | Fedoraproject |
| cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:* | 31 | Vulnerable | Fedoraproject |
- cpe:2.3:a:dovecot:dovecot:*:*:*:*:*:*:*:* Versions 2.3.9 to before 2.3.9.3 Vulnerable ·The Dovecot Project
- cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:* Versions 30 Vulnerable ·Fedoraproject
- cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:* Versions 31 Vulnerable ·Fedoraproject
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
Not affected: 4 products
- Red Hat Enterprise Linux 5
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
Timeline
- 2026-10-02 Threatist record created from CVE-2020-7957
- 2026-10-03 Alias added: GHSA-vg8f-j3m8-7g9v
References
Sources
- CVE-2020-7957 · CVE Program
- CVE-2020-7957 · NVD
- FIRST EPSS
- GHSA-vg8f-j3m8-7g9v · GitHub Advisory Database · CC BY 4.0
- CVE-2020-7957 · Red Hat security data · CC BY 4.0
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