CVE-2026-64638 json
Pre-auth reflected XSS on login screen with potential to lead to PHP code execution
published 2026-08-06 3 mo ago modified 2026-09-03 2 mo ago also EUVD-2026-54565 , GHSA-52p2-r8wf-jcrf
- 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, plus a Nuclei check
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
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 3 mo ago
Exploit prediction
0.89% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- Nuclei template WordPress Core < 7.0.3 - Preauth Reflected XSS (XSS2Shell) nuclei detection template
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
- CVE List CVE-2026-64638
- NVD CVE-2026-64638
- Maintainer advisory GHSA-52p2-r8wf-jcrf
Fencer Vulns 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.