Exim up to 4.95 auths/call_pam.c pam_converse use after free

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability has been found in Exim up to 4.95 (Mail Server Software) and classified as problematic. Affected by this vulnerability is the function pam_converse of the file auths/call_pam.c. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was published 08/07/2022. The advisory is shared at lists.exim.org. This vulnerability is known as CVE-2022-37451 since 08/06/2022. Technical details are known, but no exploit is available.

Upgrading to version 4.96 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 51be321b27825c01829dffd90f11bfff256f7e42 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.





  • free

CPE 2.3info

CPE 2.2info


VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.4

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔒



VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍


Class: Use after free
CWE: CWE-416 / CWE-119
ATT&CK: Unknown

Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒


Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Exim 4.96
Patch: 51be321b27825c01829dffd90f11bfff256f7e42


08/06/2022 CVE reserved
08/07/2022 +1 days Advisory disclosed
08/07/2022 +0 days VulDB entry created
08/31/2022 +24 days VulDB last update


Advisory: 51be321b27825c01829dffd90f11bfff256f7e42
Status: Confirmed

CVE: CVE-2022-37451 (🔒)


Created: 08/07/2022 10:49 AM
Updated: 08/31/2022 01:41 PM
Changes: 08/07/2022 10:49 AM (43), 08/31/2022 01:36 PM (1), 08/31/2022 01:41 PM (11)
Complete: 🔍


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