TP-Link Archer AX-21 Command Injection
CVE-2023-1389 is a high-severity improper neutralization of special elements used in a command vulnerability in TP-Link Archer AX21 (AX1800), with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. Affected TP-Link Archer AX21 (AX1800) versions: All versions prior to version 1.14 Build 20230219. The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on May 1, 2023, which means attacks have been observed in the wild.
Attackers are already exploiting this vulnerability, according to CISA.
What to do
- Update Archer Ax21 Firmware to 1.1.4 or a later version.
- CISA's required action: Apply updates per vendor instructions.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| TP-Link Archer AX21 (AX1800) | TP-Link Archer AX21 (AX1800) | All versions prior to version 1.14 Build 20230219 | Not stated |
| TP-Link | Archer Ax21 Firmware | before 1.1.4 | 1.1.4 |
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
- AdjacentThe attacker must be on the same local network segment.
- 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:A/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 | 8.8 | High | NVD |
| CVSS 3.1 | 8.8 | High | CISA (ADP) |
Official description
TP-Link Archer AX21 (AX1800) firmware versions before 1.1.4 Build 20230219 contained a command injection vulnerability in the country form of the /cgi-bin/luci;stok=/locale endpoint on the web management interface. Specifically, the country parameter of the write operation was not sanitized before being used in a call to popen(), allowing an unauthenticated attacker to inject commands, which would be run as root, with a simple POST request.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Special Elements used in a Command
The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component.
How developers prevent this class of flaw
- If at all possible, use library calls rather than external processes to recreate the desired functionality.
- If possible, ensure that all external commands called from the program are statically created.
- Run time: Run time policy enforcement may be used in an allowlist fashion to prevent use of any non-sanctioned commands.
More Improper Neutralization of Special Elements used in a Command vulnerabilities (CWE-77)
Timeline
- CVE record published.
- Added to CISA's Known Exploited Vulnerabilities catalogue.
- Deadline for US federal agencies to remediate, set by CISA.
- CISA published its SSVC assessment (exploitation: active, automatable: yes, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-1389US Government Resource
Technical write-ups (may include proof of concept)
- packetstormsecurity.com/files/174131/TP-Link-Archer-AX21-Command-Injection.htmlExploit, Third Party Advisory, VDB Entry
- tenable.com/security/research/tra-2023-11Exploit, Third Party Advisory
Recent Improper Neutralization of Special Elements used in a Command vulnerabilities
- 7.2 High severity
- 7.8 High severity
- 8.8 High severity
- 8.8 High severity
- 7.8 High severity
- 8.8 High severity
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