Cyber Resilience

CVE-2020-28024

Critical

Published: 06 May 2021

Published
06 May 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0551 90.4th percentile
Risk Priority 23 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2020-28024 is a critical-severity Out-of-bounds Write (CWE-787) vulnerability in Exim Exim. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 9.6% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

Exim 4 before 4.94.2 allows Buffer Underwrite that may result in unauthenticated remote attackers executing arbitrary commands, because smtp_ungetc was only intended to push back characters, but can actually push back non-character error codes such as EOF.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

exim
exim
4.00 — 4.94.2

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-787

Out-of-bounds writes that corrupt control flow or inject shellcode are rendered non-executable by the same memory protections.

References