#VU81251 Out-of-bounds read in Exim - CVE-2023-42114

Vulnerability identifier: #VU81251

Vulnerability risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2023-42114

CWE-ID: CWE-125

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Exim
Server applications / Mail servers

Vendor: Exim

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition when handling NTLM challenge requests. A remote attacker can send specially crafted data to the server, trigger an out-of-bounds read error and read contents of memory on the system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Exim: 4.00 - 4.96

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External links
https://www.zerodayinitiative.com/advisories/ZDI-23-1468/
https://www.exim.org/static/doc/security/CVE-2023-zdi.txt

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.