ZeroHour

CVE-2026-64638

mass

Pre-Auth Reflected XSS in WordPress Login Screen Can Escalate to RCE

CVSS 4.0
8.9 high
EPSS
31%p98
Published
()
Modified
AI analysis

WordPress core contains a reflected cross-site scripting (CWE-79) vulnerability on the login screen that can be triggered without authentication. An attacker must socially engineer a victim into clicking a crafted link or interacting with an attacker-hosted third-party website, so explicit user interaction is required for exploitation. If successful, the attacker can run malicious script in the victim's browser on the targeted WordPress site, and — under conditions outside the attacker's direct control — escalate the XSS to remote code execution (PHP code execution). Every version of WordPress is affected; version 7.0.3 fixes the flaw and the fix has been backported to all branches back to 4.7. No public proof-of-concept is known and the issue is not yet in CISA's KEV catalog, though EPSS assigns a 31.2% probability of exploitation within 30 days (98th percentile), indicating elevated near-term risk.

What to do: Update to WordPress 7.0.3, or apply the backported security update on your branch (backports are available for all branches back to 4.7). Until patched, exercise caution with unsolicited login-page links and consider monitoring authentication and admin-action logs for suspicious activity, since exploitation depends on user interaction. Because the RCE escalation depends on environmental conditions, treat all unpatched WordPress sites as exposed even if no in-the-wild exploitation is yet confirmed.

Affected
WordPress coreAll versions prior to 7.0.3; fixes backported to all branches back to 4.7
Estimated exposure
masstens of millions of sites (WordPress powers roughly 40%+ of all websites) — WordPress's global market share (~40%+ of all websites per public W3Techs surveys) implies an install base in the tens of millions, all of which are affected prior to patching.

Order-of-magnitude estimate by the model from install counts, market share and public scan data it knows; verify before quoting.

Description

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/).

Ecosystems
WordPress
Weakness
CWE-79
Vector
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

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