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Fencer Intel
high 8.9

CVE-2026-64638 json

Pre-auth reflected XSS on login screen with potential to lead to PHP code execution

published 3mo ago modified 2mo ago also EUVD-2026-54565 , GHSA-52p2-r8wf-jcrf

Unreviewed: the maintainers' own advisory

Published by the maintainers on their GitHub repository WordPress/wordpress-develop. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.

cvss
8.9
version 4.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.9%
EPSS 0.9% chance of exploitation in 30 days, percentile 59%
public exploits
0
none known

Summary

WordPress is vulnerable to a pre-auth reflected XSS vulnerability on the login screen.

Via a specially crafted malicious third-party website hosted by an attacker, it is possible for this to be escalated to an RCE vulnerability with conditions outside of the attackers control. This requires successful social engineering of and explicit interaction by the target victim.

This issue affects all versions of WordPress. Version 7.0.3 has been released, containing a fix for the vulnerability, and as a courtesy to users on older branches the fix has been backported to all branches back to 4.7.

Discovered and responsibly disclosed by [the team at pwn.ai](https://pwn.ai/).

Patch / fix

  • wordpress Debian 13 6.8.7+dfsg1-0+deb13u1
  • wordpress Debian 14 7.0.3+dfsg1-1

debian advisories DEBIAN-CVE-2026-64638

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
3mo ago

Exploit prediction

0.89% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 4.0 8.9 CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
CNA 4.0 8.9 CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/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

Affected products

  • WordPress WordPress

Classification

Weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation
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.

The maintainers of WordPress/wordpress-develop published their own advisory on GitHub. Reviewed sources take precedence over it.