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CVE-2023-46714NVD status: Modified

FortiOS: Stack-based Buffer Overflow

CVE-2023-46714 is a high-severity stack-based buffer overflow vulnerability in FortiOS from Fortinet, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. Affected FortiOS versions: 7.4.0 through 7.4.1; 7.2.1 through 7.2.6. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.41% chance of exploitation within 30 days, higher than 73% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of FortiOS you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on fortiguard.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
FortinetFortiOS7.4.0 through 7.4.1; 7.2.1 through 7.2.6Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
HighAdministrator-level access is required first.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.2HighCNA (fortinet.com)
CVSS 3.17.2HighNVD

Official description

A stack-based buffer overflow [CWE-121] vulnerability in Fortinet FortiOS version 7.2.1 through 7.2.6 and version 7.4.0 through 7.4.1 allows a privileged attacker over the administrative interface to execute arbitrary code or commands via crafted HTTP or HTTPs requests.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Stack-based Buffer Overflow

The product writes past the end of a buffer that was allocated on the stack.

How developers prevent this class of flaw

  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.
  • Use an abstraction library to abstract away risky APIs. Not a complete solution.
  • Implement and perform bounds checking on input.

More Stack-based Buffer Overflow vulnerabilities (CWE-121)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in FortiOS

All FortiOS vulnerabilities

Recent Stack-based Buffer Overflow vulnerabilities

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