CVE-2021-42756FortiWeb Stack Buffer Overflow
Multiple stack-based buffer overflow vulnerabilities [CWE-121] in the proxy daemon of FortiWeb 5.x all versions, 6.0.7 and below, 6.1.2 and below, 6.2.6 and below, 6.3.16 and below, 6.4 all versions may allow an unauthenticated remote attacker to achieve arbitrary code execution…
Published Feb 16, 2023 · Updated Nov 21, 2024
Key Facts
Patch in the next maintenance window- CVE-2021-42756 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting FortiWeb (Fortinet).
- It is not listed in any known-exploited vulnerabilities catalog. No public exploit code is known.
- EPSS estimates a 35% probability of exploitation in the next 30 days.
- Fixed versions are available, including FortiWeb 6.0.8, FortiWeb 5.6.*, FortiWeb 5.7.*.
- Brandefense priority: patch in the next maintenance window, because of its high severity, although no exploitation is known.
Scores
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
35%
Higher than 98.4% of all scored CVEs
Exploit maturity
None known
ATLAS score
36/100
Publication score, see How it works
Exploitation Verdict
KEV listed
Not listed
Federal due date
None
No federal due date
Ransomware use
Not reported
Attributed actors
None named
Exploit & Defence Guidance
Exploit maturity
None known
Public exploit code
0
Proof-of-concept links
In-the-wild evidence
0
Reports of active use
Advisories And Exploit References
Description
Multiple stack-based buffer overflow vulnerabilities [CWE-121] in the proxy daemon of FortiWeb 5.x all versions, 6.0.7 and below, 6.1.2 and below, 6.2.6 and below, 6.3.16 and below, 6.4 all versions may allow an unauthenticated remote attacker to achieve arbitrary code execution via specifically crafted HTTP requests.
Affected Products
2 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| FortiWebFortinet | >= 6.4.0 | 6.0.8 |
Patched Releases
FortiWeb
6.0.8, 5.6.*, 5.7.*, 5.8.*
Timeline
Publicly disclosed
Feb 16, 2023
Last updated
Nov 21, 2024
Weakness Type
- CWE-121 Stack-based Buffer Overflow
- CWE-787 Out-of-bounds Write
References
FAQ
Common Questions.
Multiple stack-based buffer overflow vulnerabilities [CWE-121] in the proxy daemon of FortiWeb 5.x all versions, 6.0.7 and below, 6.1.2 and below, 6.2.6 and below, 6.3.16 and below, 6.4 all versions may allow an unauthenticated remote attacker to achieve arbitrary code execution via specifically crafted HTTP requests.
Affected: FortiWeb (Fortinet) versions >= 6.4.0. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including FortiWeb 6.0.8, FortiWeb 5.6.*, FortiWeb 5.7.*.
Brandefense priority: patch in the next maintenance window, because of its high severity, although no exploitation is known.
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