Cyber Resilience

CVE-2023-42789

Critical

Published: 12 March 2024

Published
12 March 2024
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 0.2828 96.6th percentile
Risk Priority 37 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2023-42789 is a critical-severity Out-of-bounds Write (CWE-787) vulnerability in Fortinet Fortios. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 3.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

Deeper analysis

CVE-2023-42789 is an out-of-bounds write vulnerability, tracked under CWE-787, that affects multiple versions of Fortinet FortiOS (7.4.0 through 7.4.1, 7.2.0 through 7.2.5, 7.0.0 through 7.0.12, 6.4.0 through 6.4.14, and 6.2.0 through 6.2.15) as well as FortiProxy (7.4.0, 7.2.0 through 7.2.6, 7.0.0 through 7.0.12, and 2.0.0 through 2.0.13). The flaw carries a CVSS v3.1 score of 9.8 and permits execution of unauthorized code or commands when the affected devices process specially crafted HTTP requests.

An unauthenticated remote attacker can exploit the issue over the network without user interaction by sending malicious HTTP requests that trigger the out-of-bounds write, resulting in full compromise of confidentiality, integrity, and availability on the target device.

The Fortinet advisory FG-IR-23-328, referenced at fortiguard.com/psirt/FG-IR-23-328, supplies official guidance on mitigation and available patches for the listed FortiOS and FortiProxy releases. The associated EPSS score has remained near its observed peak of 0.3002 with a current value of 0.2828.

EU & UK References

Vulnerability details

A out-of-bounds write in Fortinet FortiOS 7.4.0 through 7.4.1, 7.2.0 through 7.2.5, 7.0.0 through 7.0.12, 6.4.0 through 6.4.14, 6.2.0 through 6.2.15, FortiProxy 7.4.0, 7.2.0 through 7.2.6, 7.0.0 through 7.0.12, 2.0.0 through 2.0.13 allows attacker to execute unauthorized code or commands…

more

via specially crafted HTTP requests.

CWE(s)

Related Threats

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

Affected Assets

fortinet
fortiproxy
7.4.0 · 2.0.0 — 2.0.13 · 7.0.0 — 7.0.12 · 7.2.0 — 7.2.6
fortinet
fortios
7.4.0, 7.4.1 · 6.2.0 — 6.2.15 · 6.4.0 — 6.4.14 · 7.0.0 — 7.0.12

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