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CVE-2023-27997KEVRansomware

Fortinet FortiOS and FortiProxy SSL-VPN Heap-Based Buffer Overflow Vulnerability

Severity
Critical9.8CVSS 3.1, Critical
EPSS
86%
Published
13 Jun 2023
Updated
31 Jul 2026

Description

Title, description and vendor guidance are quoted from the source records.

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.

Weakness: CWE-122, CWE-787

Known exploited

Added to CISA KEV on 13 Jun 2023

Federal remediation due date: 4 Jul 2023

Known use in ransomware campaigns

Required action: Apply updates per vendor instructions.

Exploit prediction

86% probability of exploitation in the next 30 days (percentile 100%).

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

What the source states, per branch

Versions matched by Patcharo

Fortinet FortiProxySource: Fortinet (CVE record)

BranchAffectedFixed in
7.2
7.2.0 – 7.2.3
Fixed after 7.2.3
7.0
7.0.0 – 7.0.9
Fixed after 7.0.9
2.0
2.0.0 – 2.0.12
Fixed after 2.0.12
1.2
1.2.0 – 1.2.13
Fixed after 1.2.13
1.1
1.1.0 – 1.1.6
Fixed after 1.1.6

Versions not listed are stated unaffected by the vendor.

Fortinet FortiOSSource: Fortinet (CVE record)

BranchAffectedFixed in
7.2
7.2.0 – 7.2.4
Fixed after 7.2.4
7.0
7.0.0 – 7.0.11
Fixed after 7.0.11
6.4
6.4.0 – 6.4.12
Fixed after 6.4.12
6.2
6.2.0 – 6.2.13
Fixed after 6.2.13
6.0
6.0.0 – 6.0.16
Fixed after 6.0.16

Versions not listed are stated unaffected by the vendor.

Affected products

  • Fortinet FortiOS-6K7K · 7.0.10, 7.0.5, 6.4.12, 6.4.10, 6.4.8, 6.4.6, 6.4.2, 6.2.9 ≤ 6.2.13, 6.2.6 ≤ 6.2.7, 6.2.4, 6.0.12 ≤ 6.0.16, 6.0.10

Workaround / Vendor remediation

Vendor remediation · FortiProxy

Please upgrade to FortiOS-6K7K version 7.0.12 or above Please upgrade to FortiOS-6K7K version 6.4.13 or above Please upgrade to FortiOS-6K7K version 6.2.15 or above Please upgrade to FortiOS-6K7K version 6.0.17 or above Please upgrade to FortiProxy version 7.2.4 or above Please upgrade to FortiProxy version 7.0.10 or above Please upgrade to FortiOS version 7.4.0 or above Please upgrade to FortiOS version 7.2.5 or above Please upgrade to FortiOS version 7.0.12 or above Please upgrade to FortiOS version 6.4.13 or above Please upgrade to FortiOS version 6.2.14 or above Please upgrade to FortiOS version 6.0.17 or above

Vendor remediation · FortiOS

Please upgrade to FortiOS-6K7K version 7.0.12 or above Please upgrade to FortiOS-6K7K version 6.4.13 or above Please upgrade to FortiOS-6K7K version 6.2.15 or above Please upgrade to FortiOS-6K7K version 6.0.17 or above Please upgrade to FortiProxy version 7.2.4 or above Please upgrade to FortiProxy version 7.0.10 or above Please upgrade to FortiOS version 7.4.0 or above Please upgrade to FortiOS version 7.2.5 or above Please upgrade to FortiOS version 7.0.12 or above Please upgrade to FortiOS version 6.4.13 or above Please upgrade to FortiOS version 6.2.14 or above Please upgrade to FortiOS version 6.0.17 or above

References

Provenance

Every fact on this page comes from the sources below. Nothing is written by an AI.

Fortinet (CVE record)
Fortinet (CVE record) · 27 Sept 2026, 23:46 UTC · Parser patcharo-cve5/1.1.0
CISA Known Exploited Vulnerabilities
CISA Known Exploited Vulnerabilities · 27 Sept 2026, 23:42 UTC · Parser patcharo-kev/1.0.0
NVD
NVD · 27 Sept 2026, 23:44 UTC · Parser patcharo-nvd/1.0.0
FIRST EPSS
FIRST EPSS · 27 Sept 2026, 23:46 UTC · Parser patcharo-epss/1.0.0

Last verified: 28 Sept 2026, 02:31 UTC