Exim DMARC dmarc.c dmarc_dns_lookup use after free

published 2022-10-20 4 y ago modified 2026-06-17 4 mo ago also EUVD-2022-42980

cvss: 5.6; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.0%; EPSS 1.0% chance of exploitation in 30 days, percentile 63%
public exploits: 0; none known

A vulnerability was found in Exim and classified as problematic. This issue affects the function dmarc_dns_lookup of the file dmarc.c of the component DMARC Handler. The manipulation leads to use after free. The attack may be initiated remotely. The name of the patch is 12fb3842f81bcbd4a4519d5728f2d7e0e3ca1445. It is recommended to apply a patch to fix this issue. The associated identifier of this vulnerability is VDB-211919.

Patch / fix

fixed in 1 distros 1 links 1

exim exim 4.97

exim4 Debian 14, Debian 13, Debian 12 4.96-7

debian advisories DEBIAN-CVE-2022-3620

git.exim.org/exim.git/commit/12fb3842f81bcbd4a4519d5728f2d7e0e3ca1445 commit

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2022-3620 updated 2026-06-26

exim: UAF in dmarc_dns_lookup

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 18 mo ago (2025-04-14)

Exploit prediction

1.01% chance of exploitation in the next 30 days, higher than 63% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.6	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
NVD	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

unspecified Exim

Classification

Weakness

CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer
CWE-416 Use After Free

References

git.exim.org /exim.git/commit/12fb3842f81bcbd4a4519d5728f2d7e0e3ca1445
mailing-list, patch, vendor-advisory
lists.fedoraproject.org /archives/list/package-announce%40lists.fedoraproject.org/message/XV2K2AWF62FSJ64B5CUZPFT4COK7P5PM/
vendor-advisory, third-party-advisory
lists.fedoraproject.org /archives/list/package-announce%40lists.fedoraproject.org/message/667V3ADXQ2MHUJMSXA3VZZEWLVSCIBEU/
vendor-advisory, third-party-advisory
lists.fedoraproject.org /archives/list/package-announce%40lists.fedoraproject.org/message/EIH4W5R7SHTUEQFWWKB4TUO5YFZX64KV/
vendor-advisory, third-party-advisory
vuldb.com /?id.211919
third-party-advisory

Sources

CVE List CVE-2022-3620
NVD CVE-2022-3620

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary