CVE-2023-27997: Fortinet FortiOS and FortiProxy SSL-VPN Heap-Based Buffer Overflow
This Fortinet advisory covers CVE-2023-27997 in FortiOS-6K7K and FortiProxy.
- CVE-2023-27997
Key facts
- Vendor rating
- Critical, CVSS 9.8
- CISA KEV
- Listed ; federal due date ; ransomware use known to CISA
- Affected
- FortiOS: 6.0.0 through 7.2.4 (vendor-listed versions); FortiOS-6K7K: 6.0.10 through 7.0.10 (vendor-listed versions); FortiProxy: 1.1.0 through 7.2.3 (vendor-listed versions)
- Fixed in
- FortiOS 7.2: 7.2.5, FortiOS 7.0: 7.0.12, FortiOS 6.4: 6.4.13 and 11 more below
- Source published
- Source revised
- Listed by VulniPulse
Compiled by VulniPulse from the linked sources. How records are collected and checked.
Affected products & platforms
CVE-2023-27997 in the CISA Known Exploited Vulnerabilities catalog
- CISA name:
- Fortinet FortiOS and FortiProxy SSL-VPN Heap-Based Buffer Overflow Vulnerability
- CISA description:
- Fortinet FortiOS and FortiProxy SSL-VPN contain a heap-based buffer overflow vulnerability which can allow an unauthenticated, remote attacker to execute code or commands via specifically crafted requests.
- Required action:
- Apply updates per vendor instructions.
Description
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.
Affected products named by the advisory: FortiOS-6K7K.
Text from the source record.
- FortiOS: 6.0.0 through 7.2.4 (vendor-listed versions)
- FortiOS-6K7K: 6.0.10 through 7.0.10 (vendor-listed versions)
- FortiProxy: 1.1.0 through 7.2.3 (vendor-listed versions)
Official advisory · high-confidence parse· fetched ·verify at source
How to fix CVE-2023-27997
Upgrade to a fixed release named by Fortinet:
- FortiOS 7.2: 7.2.5
- FortiOS 7.0: 7.0.12
- FortiOS 6.4: 6.4.13
- FortiOS 6.2: 6.2.14
- FortiOS 6.0: 6.0.17
- FortiOS-6K7K 7.0: 7.0.12
- FortiOS-6K7K 6.4: 6.4.13
- FortiOS-6K7K 6.2: 6.2.15
- FortiOS-6K7K 6.0: 6.0.17
- FortiProxy 7.2: 7.2.4
- FortiProxy 7.0: 7.0.10
- FortiProxy 2.0: 2.0.13
- FortiProxy 1.2: migrate to a fixed release
- FortiProxy 1.1: migrate to a fixed release
Vendor guidance
- Upgrade per the Affected/Solution table: FortiOS 7.2: 7.2.5; FortiOS 7.0: 7.0.12; FortiOS 6.4: 6.4.13; FortiOS 6.2: 6.2.14; FortiOS 6.0: 6.0.17; ….
Workarounds
- Disable SSL-VPN.
Support dates for the fixed release lines
- Fortinet FortiOS 7.2: support ended
- Fortinet FortiOS 7.0: support ended
- Fortinet FortiOS 6.4: support ended
- Fortinet FortiOS 6.2: support ended
- Fortinet FortiOS 6.0: support ended
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