Administrator-level stored XSS via unescaped directive rendering
Published Apr 22, 2026 · Updated Apr 22, 2026
Stored XSS in Dimitar Ivanov HTTP Headers 1.19.4 and earlier allows remote authenticated users to execute scripts via custom headers. The Manual settings view writes Apache and Nginx directive arrays into HTML textarea elements with raw join output, allowing a stored value to terminate the textarea and inject script markup. Administrator access is required, and exposure is limited to multisite installations or sites where unfiltered_html is disabled.
Summary
What happened
Stored XSS in Dimitar Ivanov HTTP Headers 1.19.4 and earlier allows remote authenticated users to execute scripts via custom headers. The Manual settings view writes Apache and Nginx directive arrays into HTML textarea elements with raw join output, allowing a stored value to terminate the textarea and inject script markup. Administrator access is required, and exposure is limited to multisite installations or sites where unfiltered_html is disabled.
The record
- CVE
- CVE-2026-1379
- Published
- Apr 22, 2026
- Updated
- Apr 22, 2026
- Vendor
- Dimitar Ivanov
- Product
- HTTP Headers
- Classifications
- CWE-79, T1059.007
- Attack vector
- network
- Privileges
- admin
Timeline
How it unfolded
- Apr 22, 2026CVE publishedPublication date reported by the CVE source.
- Apr 22, 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=0 <=1.19.2
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
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Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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