Buffer overflow in Exim
CVE-2023-42116
Exim SMTP Challenge Stack-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Exim. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of NTLM challenge requests. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of the service account. . Was ZDI-CAN-17515.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.038 (89.7th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 90th percentile — 89.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.032 · newest: 0.038 · change: +0.006
Affected products
- Exim — versions exim 4.95
Weakness classification (CWE)
Public proof-of-concept exploits
References
- www.zerodayinitiative.com/advisories/ZDI-23-1470/ (x_research-advisory, Third Party Advisory)
- af854a3a-2127-422b-91ae-364da2661108
Frequently asked questions
- What is CVE-2023-42116?
- CVE-2023-42116 is a critical-severity vulnerability in Exim, classified under Stack-based Buffer Overflow. CVSS score: 9.8/10. Published 2024-05-03.
- How severe is CVE-2023-42116?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2023-42116 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.