FortiOS: Double Free
CVE-2023-41678 is a high-severity double free vulnerability in FortiOS from Fortinet, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected FortiOS versions: 7.0.0 through 7.0.5. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.07% chance of exploitation within 30 days, higher than 65% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of FortiOS you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on fortiguard.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Fortinet | FortiOS | 7.0.0 through 7.0.5 | Not stated |
| Fortinet | FortiPAM | 1.1.0 through 1.1.1; 1.0.0 through 1.0.3 | Not 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
- LowA basic user account is enough.
- 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:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 8.8 | High | CNA (fortinet.com) |
| CVSS 3.1 | 8.8 | High | NVD |
Official description
A double free in Fortinet FortiOS versions 7.0.0 through 7.0.5, FortiPAM version 1.0.0 through 1.0.3, 1.1.0 through 1.1.1 allows attacker to execute unauthorized code or commands via specifically crafted request.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Double Free
The product calls free() twice on the same memory address.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- Ensure that each allocation is freed only once. After freeing a chunk, set the pointer to NULL to ensure the pointer cannot be freed again. In complicated error conditions, be sure that clean-up routines respect the state of allocation properly. If the language is object oriented, ensure that object destructors delete each chunk of memory only once.
- Use a static analysis tool to find double free instances.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other vulnerabilities in FortiOS
- 9.8 Critical severity
- 7.5 High severity
- 7.4 High severity
- 7.4 High severity
- 9.6 Critical severity
- 9.3 Critical severity
Recent Double Free vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 9.8 Critical severity
- 8.8 High severity
- 7.5 High severity
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