Administrator session compromise via SVG filter bypass
Published May 11, 2026 · Updated May 11, 2026
Stored XSS in Grav before 2.0.0-beta.2 allows remote authenticated users with page-edit rights to execute script in an administrator's browser. Security::detectXss fails to reject unquoted event handlers, while the default dangerous-tag list omits SVG and related scripting-capable elements. Exploitation requires a page editor to store crafted content and a Super Admin to visit it, exposing the administrator session context and enabling further privileged actions.
Summary
What happened
Stored XSS in Grav before 2.0.0-beta.2 allows remote authenticated users with page-edit rights to execute script in an administrator's browser. Security::detectXss fails to reject unquoted event handlers, while the default dangerous-tag list omits SVG and related scripting-capable elements. Exploitation requires a page editor to store crafted content and a Super Admin to visit it, exposing the administrator session context and enabling further privileged actions.
The record
- CVE
- CVE-2026-42611
- Published
- May 11, 2026
- Updated
- May 11, 2026
- Vendor
- Grav
- Product
- Grav
- Classifications
- CWE-79, T1190
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- May 11, 2026CVE publishedPublication date reported by the CVE source.
- May 11, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 2.0.0-beta.2
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Vendor advisory stored-XSS proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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