Mt6000 Firmware: Improper Limitation of a Pathname to a Restricted Directory
CVE-2024-39226 is a critical-severity improper limitation of a pathname to a restricted directory vulnerability in Mt6000 Firmware from GL.iNet, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Mt6000 Firmware versions: 4.5.8. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 20.4% chance of exploitation within 30 days, which is in the top 2.47% of all scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of Mt6000 Firmware you run against the affected versions below, and install the vendor's latest release.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Gl-inet | Mt6000 Firmware | 4.5.8 | Not stated |
| Gl-inet | A1300 Firmware | 4.5.16 | Not stated |
| Gl-inet | X300b Firmware | 4.5.16 | Not stated |
| Gl-inet | Ax1800 Firmware | 4.5.16 | Not stated |
| Gl-inet | Axt1800 Firmware | 4.5.16 | Not stated |
| Gl-inet | Mt2500 Firmware | 4.5.16 | Not stated |
| Gl-inet | Mt3000 Firmware | 4.5.16 | Not stated |
| Gl-inet | X3000 Firmware | 4.4.8 | Not stated |
| Gl-inet | Xe3000 Firmware | 4.4.8 | Not stated |
| Gl-inet | Xe300 Firmware | 4.3.16 | Not stated |
| Gl-inet | E750 Firmware | 4.3.12 | Not stated |
| Gl-inet | X750 Firmware | 4.3.11 | Not stated |
| Gl-inet | Sft1200 Firmware | 4.3.11 | Not stated |
| Gl-inet | Ar300m Firmware | 4.3.11 | Not stated |
| Gl-inet | Ar300m16 Firmware | 4.3.11 | Not stated |
| Gl-inet | Ar750 Firmware | 4.3.11 | Not stated |
| Gl-inet | Ar750s Firmware | 4.3.11 | Not stated |
| Gl-inet | B1300 Firmware | 4.3.11 | Not stated |
| Gl-inet | Mt1300 Firmware | 4.3.11 | Not stated |
| Gl-inet | Mt300n-v2 Firmware | 4.3.11 | Not stated |
| Gl-inet | Ap1300 Firmware | 3.217 | Not stated |
| Gl-inet | B2200 Firmware | 3.216 | Not stated |
| Gl-inet | Mv1000 Firmware | 3.216 | Not stated |
| Gl-inet | Mv1000w Firmware | 3.216 | Not stated |
| Gl-inet | Usb150 Firmware | 3.216 | Not stated |
Version data comes from NVD's product matching; 3 further products are omitted here. 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
- NoneNo account or login is needed.
- 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:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 9.8 | Critical | NVD |
| CVSS 3.1 | 4.3 | Medium | CISA (ADP) |
Official description
GL-iNet products AR750/AR750S/AR300M/AR300M16/MT300N-V2/B1300/MT1300/SFT1200/X750 v4.3.11, MT3000/MT2500/AXT1800/AX1800/A1300/X300B v4.5.16, XE300 v4.3.16, E750 v4.3.12, AP1300/S1300 v4.3.13, and XE3000/X3000 v4.4 were discovered to contain a vulnerability can be exploited to manipulate routers by passing malicious shell commands through the s2s API.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Limitation of a Pathname to a Restricted Directory
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
How developers prevent this class of flaw
- For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
- Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.
More Improper Limitation of a Pathname to a Restricted Directory vulnerabilities (CWE-22)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Technical write-ups (may include proof of concept)
- github.com/gl-inet/CVE-issues/blob/main/4.0.0/s2s%20interface%20shell%20injection.mdExploit, Third Party Advisory
Other vulnerabilities in Mt6000 Firmware
- 8.8 High severity
- 8.8 High severity
- 8.0 High severity
- 8.0 High severity
- 9.8 Critical severity
- 9.8 Critical severity
Recent Improper Limitation of a Pathname to a Restricted Directory vulnerabilities
- 8.8 High severity
- 8.8 High severity
- 9.8 Critical severity
- 8.8 High severity
- 7.2 High severity
- 9.8 Critical severity
Spotted an error? Tell us.