A3300R: Improper Neutralization of Special Elements used in a Command
CVE-2026-5104 is a high-severity improper neutralization of special elements used in a command vulnerability in A3300R from TOTOLINK, 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 A3300R versions: 17.0.0cu.557_b20221024. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 2.78% chance of exploitation within 30 days, higher than 87% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of A3300R you run against the affected versions below, and install the vendor's latest release.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| TOTOLINK | A3300R | 17.0.0cu.557_b20221024 | Not stated |
| TOTOLINK | A3300r Firmware | 17.0.0cu.557_b20221024 | 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 4.0 | 2.1 | Low | CNA (vuldb.com) |
| CVSS 3.1 | 6.3 | Medium | CNA (vuldb.com) |
| CVSS 3.1 | 8.8 | High | NVD |
| CVSS 2.0 | 6.5 | Medium | CNA (vuldb.com) |
Official description
A security vulnerability has been detected in Totolink A3300R 17.0.0cu.557_b20221024. Impacted is the function setStaticRoute of the file /cgi-bin/cstecgi.cgi. Such manipulation of the argument ip leads to command injection. The attack may be performed from remote. The exploit has been disclosed publicly and may be used.
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.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- vuldb.com/vuln/354129Third Party Advisory, VDB Entry
- vuldb.com/vuln/354129/ctiThird Party Advisory, VDB Entry
Technical write-ups (may include proof of concept)
- github.com/LvHongW/Vuln-of-totolink_A3300R/tree/main/A3300R_ip_cmd_injectExploit, Third Party Advisory
Other references
- vuldb.com/submit/779142Permissions Required, VDB Entry
- totolink.net/Product
Other vulnerabilities in A3300R
- 8.8 High severity
- 8.8 High severity
- 9.8 Critical severity
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
Recent Improper Neutralization of Special Elements used in a Command vulnerabilities
- 8.8 High severity
- 10.0 Critical severity
- 9.8 Critical severity
- 9.8 Critical severity
- 7.3 High severity
- 8.8 High severity
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