Broken Link Checker < 2.4.12 - Unauthenticated RCE via Query Variable Injection
Priority MEDIUM 45CWE-94Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-94.
Summary
The Broken Link Checker WordPress plugin before 2.4.12 does not limit which query variables it accepts from user input on sites using plain permalinks, allowing unauthenticated users to overwrite arbitrary PHP global variables, and to execute arbitrary code on the server when a classic (non-block) is active.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01993 80th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA
Fix Fixed Broken Link Checker (Unknown): 2.4.12
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Unknown | Broken Link Checker | before 2.4.12 | 2.4.12 | Patch available | CNA |
- Broken Link Checker VendorUnknown Affected before 2.4.12 Fixed in 2.4.12 Patch available CNA
Remediation
- Fix · CNA Broken Link Checker (Unknown) Fixed in 2.4.12
Timeline
- 2026-10-02 Threatist record created from CVE-2026-18937
- 2026-10-03 Alias added: GHSA-c2xc-88v3-37g2
- 2026-10-23 EPSS moved to the 50th–90th percentile
References
Sources
- CVE-2026-18937 · CVE Program
- CVE-2026-18937 · NVD
- FIRST EPSS
- GHSA-c2xc-88v3-37g2 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences