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CVE-2026-121931

8.5 high

High (8.5).

On this page
A security vulnerability has been detected in Linksys WRT54GL 4.30.18. The impacted element is the function system of the file apply.cgi of the component Traceroute Diagnostic Function. Such manipulation of the argument traceroute_ip leads to os command injection. The attack can be launched remotely. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way. This vulnerability only affects products that are no longer supported by the maintainer.

Severity

CVSS 4.0

8.5 high
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P

CVSS 3.1

9.1 critical
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
CWEs
CWE-77 Improper Neutralization of Special Elements used in a Command
CWE-78 Improper Neutralization of Special Elements used in an OS Command (OS Command Injection)
OWASP Top 10
A05:2025 Injection
Published
Modified
Record from
the NVD, synced

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Versions

From the CNA's record in the CVE List.

ProductAffected
Linksys WRT54GL4.30.18

Attack patterns (CAPEC)

  • CAPEC-6 Argument Injection Likelihood: High · Severity: High
  • CAPEC-15 Command Delimiters Likelihood: High · Severity: High
  • CAPEC-43 Exploiting Multiple Input Interpretation Layers Likelihood: Medium · Severity: High
  • CAPEC-88 OS Command Injection Likelihood: High · Severity: High
  • CAPEC-108 Command Line Execution through SQL Injection Likelihood: Low · Severity: Very High
  • CAPEC-40 Manipulating Writeable Terminal Devices Likelihood: High · Severity: Very High
  • CAPEC-75 Manipulating Writeable Configuration Files Likelihood: High · Severity: Very High
  • CAPEC-76 Manipulating Web Input to File System Calls Likelihood: High · Severity: Very High
  • CAPEC-136 LDAP Injection Likelihood: High · Severity: High
  • CAPEC-183 IMAP/SMTP Command Injection Severity: Medium

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits. More on the page of CWE-77.

References

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