CVE-2026-121930
Linksys WRT54GL Ping Diagnostic apply.cgi system os command injection
A weakness has been identified in Linksys WRT54GL 4.30.18. The affected element is the function system of the file apply.cgi of the component Ping Diagnostic. This manipulation of the argument ping_ip causes os command injection. The attack can be initiated remotely. The exploit has been made available to the public and could be used for attacks. 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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- High
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Linksys WRT54GL Ping Diagnostic apply.cgi system os command injection
A weakness has been identified in Linksys WRT54GL 4.30.18. The affected element is the function system of the file apply.cgi of the component Ping Diagnostic. This manipulation of the argument ping_ip causes os command injection. The attack can be initiated remotely. The exploit has been made available to the public and could be used for attacks. 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.
- Record
CVE-2026-121930- CVSS 4.0
- 9.4 Critical
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/E:P/RL:X/RC:R - CVSS 3.0
- 9.1 Critical
CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H/E:P/RL:X/RC:R - CVSS 2.0
- 8.3
AV:N/AC:L/Au:M/C:C/I:C/A:C/E:POC/RL:ND/RC:UR - Weakness
- CWE-78, CWE-77
- Updated
- 2026-11-04
EUVDEUVD-2026-117019
A weakness has been identified in Linksys WRT54GL 4.30.18. The affected element is the function system of the file apply.cgi of the component Ping Diagnostic. This manipulation of the argument ping_ip causes os command injection. The attack can be initiated remotely. The exploit has been made available to the public and could be used for attacks. 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.
- Record
EUVD-2026-117019- CVSS 4.0
- 9.4 Critical
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 - Updated
- 2026-11-05
GitHub AdvisoriesGHSA-mm59-x26v-4g52
A weakness has been identified in Linksys WRT54GL 4.30.18. The affected element is the function...
A weakness has been identified in Linksys WRT54GL 4.30.18. The affected element is the function system of the file apply.cgi of the component Ping Diagnostic. This manipulation of the argument ping_ip causes os command injection. The attack can be initiated remotely. The exploit has been made available to the public and could be used for attacks. 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.
- Record
GHSA-mm59-x26v-4g52- 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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - 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 - Weakness
- CWE-77
- Updated
- 2026-11-04
NVD
A weakness has been identified in Linksys WRT54GL 4.30.18. The affected element is the function system of the file apply.cgi of the component Ping Diagnostic. This manipulation of the argument ping_ip causes os command injection. The attack can be initiated remotely. The exploit has been made available to the public and could be used for attacks. 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.
- Record
CVE-2026-121930- 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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - 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 - CVSS 2.0
- 8.3 High
AV:N/AC:L/Au:M/C:C/I:C/A:C - Weakness
- CWE-77, CWE-78
- Updated
- 2026-11-04
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| published | EUVD | |
| published | EUVD | |
| aliases, references | GitHub Advisories, NVD | |
| cwes, references, severity, title | CVE List | |
| first indexed | EUVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-121930 is a critical vulnerability (CVSS 9.4) in Linksys Wrt54gl, published November 4, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.72%, the 86th percentile. No source names a fixed version.