CVE-2023-27997criticalunder attackransomwareCWE-122

CVE-2023-27997: critical vulnerability in Fortinet FortiOS

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100Vexday Risk Score

Prioritize patching. It under exploitation confirmed by CISA, has an official Brazilian government alert and has a public proof of concept.

ssvc Actcvss 9.2epss 87%
from disclosure to weapon3 days
Published on NVDJun 13
1st PoC+3d
CISA KEVJun 13
Official alert in Brazil

Brazil's federal government published an alert, recommendation or bulletin that cites this vulnerability.

Source: CTIR Gov (GSI) and CISC Gov.br, under the CC BY-ND 3.0 license.
Action required by CISAfederal deadline: 2023-07-04

Apply updates per vendor instructions.

In short

A heap memory overflow flaw in FortiOS and FortiProxy SSL-VPN allows a remote attacker to execute malicious code by sending specially crafted requests, without needing to log in first.

Technical detail

Heap-based buffer overflow in SSL-VPN component (CWE-122) triggered by specially crafted remote requests enables arbitrary code execution. Attack vector is network-based with no authentication required; vulnerable versions span FortiOS 7.2.4 and below, 7.0.11 and below, 6.4.12 and below, 6.0.16 and below, and multiple FortiProxy versions.

Summary generated and translated by AI from the official description.

The full analysis of this CVE is available in Portuguese →

A heap-based buffer overflow vulnerability [CWE-122] in FortiOS version 7.2.4 and below, version 7.0.11 and below, version 6.4.12 and below, version 6.0.16 and below and FortiProxy version 7.2.3 and below, version 7.0.9 and below, version 2.0.12 and below, version 1.2 all versions, version 1.1 all versions SSL-VPN may allow a remote attacker to execute arbitrary code or commands via specifically crafted requests.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:F/RL:X/RC:R
Affected products
Fortinet · FortiOSFortinet · FortiOS-6K7KFortinet · FortiProxy
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