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Fencer Intel
critical 9.0

CVE-2026-18937 json

Broken Link Checker < 2.4.12 - Unauthenticated RCE via Query Variable Injection

published 2mo ago modified 4h ago also EUVD-2026-62285

cvss
9.0
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
2.0%
EPSS 2.0% chance of exploitation in 30 days, percentile 80%
public exploits
0
none known, plus a Nuclei check

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.

Patch / fix

  • Unknown Broken Link Checker 2.4.12

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
2mo ago

Exploit prediction

1.99% chance of exploitation in the next 30 days, higher than 80% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • Nuclei template WordPress Broken Link Checker < 2.4.12 - Remote Code Execution nuclei detection template
  • wpscan.com https://wpscan.com/vulnerability/a23b76eb-107d-4e02-8eae-c3c5fa5b003d/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CISA ADP 3.1 9.0 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
CNA 3.1 9.0 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

Affected products

  • Unknown Broken Link Checker

Classification

Weakness
  • CWE-94 Improper Control of Generation of Code
Technology feeds

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.