How severe is CVE-2022-37451?

CVE-2022-37451 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2022-37451 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-37451?

CVE-2022-37451 primarily affects Exim. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2022-37451?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2022-37451 published?

CVE-2022-37451 was published on 2022-08-06 and last updated on 2026-06-17.

CVE-2022-37451

CVE-2022-37451 is a high-severity vulnerability in Exim with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-763.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 3% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-763
Affected product: Exim
Published: 2022-08-06
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2022-37451?: 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.
How severe is CVE-2022-37451?: CVE-2022-37451 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2022-37451 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-37451?: CVE-2022-37451 primarily affects Exim. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2022-37451?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2022-37451 published?: CVE-2022-37451 was published on 2022-08-06 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:exim:exim:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*

More vulnerabilities in Exim

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CVE-2023-42115 — Critical (CVSS 9.8): Exim AUTH Out-Of-Bounds Write Remote Code Execution Vulnerability. This vulnerability allows remote attackers to…
CVE-2022-37452 — Critical (CVSS 9.8): Exim before 4.95 has a heap-based buffer overflow for the alias list in host_name_lookup in host.c when…
CVE-2020-28026 — Critical (CVSS 9.8): Exim 4 before 4.94.2 has Improper Neutralization of Line Delimiters, relevant in non-default configurations that enable…

All CVEs affecting Exim →

Other CWE-763 vulnerabilities

CVE-2026-52993 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: tipc: fix double-free in…
CVE-2025-14233 — Critical (CVSS 9.8): Invalid free in CPCA file deletion processing on Small Office Multifunction Printers and Laser Printers(*) which may…
CVE-2024-44852 — Critical (CVSS 9.8): Open Robotics Robotic Operating System 2 ROS2 navigation2 v.humble was discovered to contain a segmentation violation…
CVE-2021-42377 — Critical (CVSS 9.8): An attacker-controlled pointer free in Busybox's hush applet leads to denial of service and possible code execution…
CVE-2021-30473 — Critical (CVSS 9.8): aom_image.c in libaom in AOMedia before 2021-04-07 frees memory that is not located on the heap.
CVE-2021-24028 — Critical (CVSS 9.8): An invalid free in Thrift's table-based serialization can cause the application to crash or potentially result in code…

Browse all CWE-763 vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

193.202.11.112 (ipv4-addr)
76.12.128.249 (ipv4-addr)
50.116.72.139 (ipv4-addr)
166.62.41.190 (ipv4-addr)
160.187.147.124 (ipv4-addr)
132.148.155.138 (ipv4-addr)
77.221.151.241 (ipv4-addr)
37.221.254.200 (ipv4-addr)