CVE-2020-12673

Name: CVE-2020-12673
Creator: NVD / NIST
Published: 2020-08-12T16:15:11.823+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 6.19%

Last modified Jun 17, 2026

CVE-2020-12673 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. In Dovecot before 2.3.11.3, sending a specially formatted NTLM request will crash the auth service because of an out-of-bounds read.. EPSS estimates a 6.19% chance of exploitation in the next 30 days.

Description

In Dovecot before 2.3.11.3, sending a specially formatted NTLM request will crash the auth service because of an out-of-bounds read.

Metrics

CVSS 3.1

7.5/10

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

EPSS Probability

6.19%

92.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-125

Affected Software

Vendor	Product	Versions
Dovecot	Dovecot	< 2.3.11.3
Debian	Debian Linux	9.0
Debian	Debian Linux	10.0
Canonical	Ubuntu Linux	14.04
Canonical	Ubuntu Linux	16.04
Canonical	Ubuntu Linux	18.04
Canonical	Ubuntu Linux	20.04
Fedoraproject	Fedora	31
Fedoraproject	Fedora	32
Fedoraproject	Fedora	33

References

http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00048.htmlBroken Link
http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00059.htmlBroken Link
https://dovecot.org/securityVendor Advisory
https://lists.debian.org/debian-lts-announce/2020/08/msg00024.htmlThird Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4AAX2MJEULPVSRZOBX3PNPFSYP4FM4TT/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EYZU6CHA3VMYYAUCMHSCCQKJEVEIKPQ2/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XKKAL3OMG76ZZ7CIEMQP2K6KCTD2RAKE/
https://security.gentoo.org/glsa/202009-02Third Party Advisory
https://usn.ubuntu.com/4456-1/Third Party Advisory
https://usn.ubuntu.com/4456-2/Third Party Advisory
https://www.debian.org/security/2020/dsa-4745Third Party Advisory
https://www.openwall.com/lists/oss-security/2020/08/12/2Exploit, Mailing List, Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00048.htmlBroken Link
http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00059.htmlBroken Link
https://dovecot.org/securityVendor Advisory
https://lists.debian.org/debian-lts-announce/2020/08/msg00024.htmlThird Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4AAX2MJEULPVSRZOBX3PNPFSYP4FM4TT/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EYZU6CHA3VMYYAUCMHSCCQKJEVEIKPQ2/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XKKAL3OMG76ZZ7CIEMQP2K6KCTD2RAKE/
https://security.gentoo.org/glsa/202009-02Third Party Advisory
https://usn.ubuntu.com/4456-1/Third Party Advisory
https://usn.ubuntu.com/4456-2/Third Party Advisory
https://www.debian.org/security/2020/dsa-4745Third Party Advisory
https://www.openwall.com/lists/oss-security/2020/08/12/2Exploit, Mailing List, Third Party Advisory

Timeline

Published: Aug 12, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-12673?

In Dovecot before 2.3.11.3, sending a specially formatted NTLM request will crash the auth service because of an out-of-bounds read.

How severe is CVE-2020-12673?

CVE-2020-12673 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 6.19% probability of exploitation in the next 30 days.

How do I fix CVE-2020-12673?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-12673?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST