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Vulnerability record · CVE-2020-10958 · published 18 May 2020

CVE-2020-10958: Dovecot use after free vulnerability

Dovecot · Dovecot

In Dovecot before 2.3.10.1, a crafted SMTP/LMTP message triggers an unauthenticated use-after-free bug in submission-login, submission, or lmtp, and can lead to a crash under circumstances involving many newlines after a command.

5.3 CVSS 3.1 Medium EPSS 6.1% · top 6.8% CWE-416 · Use after free
5.3CVSS 3.1 base score, v2 5.0
6.1%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
20References, 2 tagged exploit
17 Jun 2026Last modified by NVD

Description

In Dovecot before 2.3.10.1, a crafted SMTP/LMTP message triggers an unauthenticated use-after-free bug in submission-login, submission, or lmtp, and can lead to a crash under circumstances involving many newlines after a command.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00059.html
http://packetstormsecurity.com/files/157771/Open-Xchange-Dovecot-2.3.10-Null-Pointer-Dereference-Denial-Of-Service.html
http://seclists.org/fulldisclosure/2020/May/37 ExploitThird Party Advisory
http://www.openwall.com/lists/oss-security/2020/05/18/1 Mailing ListThird Party Advisory
https://dovecot.org/security Vendor Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TTZN2VW55ZC2AQBGBJMLRJS
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VVUWHUUAFPC6XGIXYFIPTNB
https://usn.ubuntu.com/4361-1/
https://www.debian.org/security/2020/dsa-4690
https://www.openwall.com/lists/oss-security/2020/05/18/1 Mailing ListThird Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00059.html
http://packetstormsecurity.com/files/157771/Open-Xchange-Dovecot-2.3.10-Null-Pointer-Dereference-Denial-Of-Service.html
http://seclists.org/fulldisclosure/2020/May/37 ExploitThird Party Advisory
http://www.openwall.com/lists/oss-security/2020/05/18/1 Mailing ListThird Party Advisory
https://dovecot.org/security Vendor Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TTZN2VW55ZC2AQBGBJMLRJS
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VVUWHUUAFPC6XGIXYFIPTNB
https://usn.ubuntu.com/4361-1/
https://www.debian.org/security/2020/dsa-4690
https://www.openwall.com/lists/oss-security/2020/05/18/1 Mailing ListThird Party Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2020-10958), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.