CVE-2022-37451

Exp

Exim before 4.96 has an invalid free in pam_converse in auths/call_pam.c because store_free is not used after store_malloc.

Published: 2022-08-06 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2022-37451 is rated High Exploit Risk (77.6/100): CVSS High severity, with high exploitation likelihood (EPSS 6.73%, 91th percentile). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2022-37451

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2022-37451

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-28 6.07% 6.73% +0.66%
2 2026-01-13 5.41% 6.07% +0.66%
3 2025-12-28 — 5.41% —

Full EPSS history (29 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2022-37451

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2022-37451

OS Trackers for CVE-2022-37451

vendor priority summary link
alpine high CVE-2022-37451: 1 source package rows (exim); 22 state rows across 2 repos (3.22-community, edge-community); fixed 0, open 22. https://security.alpinelinux.org/vuln/CVE-2022-37451
debian unimportant CVE-2022-37451 unimportant priority: Debian including 1 source packages (exim4), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2022-37451
redhat medium — https://access.redhat.com/security/cve/CVE-2022-37451
ubuntu medium CVE-2022-37451 medium priority: Ubuntu including 1 source packages (exim4), 7 status rows across 7 suites (bionic, focal, jammy, kinetic, trusty, upstream, xenial): not-affected 6, released 1. https://ubuntu.com/security/CVE-2022-37451

Affected software / configurations for CVE-2022-37451

Vendor Product Version Raw CPE
exim exim < 4.96 cpe:2.3:a:exim:exim:*:*:*:*:*:*:*:*
fedoraproject fedora 35 cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
fedoraproject fedora 36 cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*

References for CVE-2022-37451

URL Tags
https://cwe.mitre.org/data/definitions/762.html Third Party Advisory
https://github.com/Exim/exim/commit/51be321b27825c01829dffd90f11bfff256f7e42 Patch Third Party Advisory
https://github.com/Exim/exim/compare/exim-4.95...exim-4.96 Release Notes Third Party Advisory
https://github.com/Exim/exim/wiki/EximSecurity Release Notes Third Party Advisory
https://github.com/ivd38/exim_invalid_free Exploit Patch Third Party Advisory
https://lists.exim.org/lurker/message/20220625.141825.d6de6074.en.html Mailing List Release Notes Vendor Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LETR5CVDPFOFQHXCJP6NFLG52JZHQYDY/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XSWDF4QEXD4TDWQLYQOWCHBJKTDQR4Z7/
https://www.exim.org/static/doc/security/ Vendor Advisory
https://www.openwall.com/lists/oss-security/2022/08/06/1 Mailing List Third Party Advisory
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