Unauthenticated content manipulation via forged unsigned tokens
Published Feb 25, 2026 · Updated Feb 25, 2026
Missing authorization in WPGSI: Spreadsheet Integration 3.8.3 and earlier allows remote attackers to alter WordPress content. The wpgsi_callBackFuncAccept and wpgsi_callBackFuncUpdate REST callbacks accept requests unconditionally, then trust unsigned Base64-encoded user data. Exploitation requires the administrator email and an active integration with remote updates enabled, and permits creation, modification, or deletion of posts and pages.
Summary
What happened
Missing authorization in WPGSI: Spreadsheet Integration 3.8.3 and earlier allows remote attackers to alter WordPress content. The wpgsi_callBackFuncAccept and wpgsi_callBackFuncUpdate REST callbacks accept requests unconditionally, then trust unsigned Base64-encoded user data. Exploitation requires the administrator email and an active integration with remote updates enabled, and permits creation, modification, or deletion of posts and pages.
The record
- CVE
- CVE-2026-1916
- Published
- Feb 25, 2026
- Updated
- Feb 25, 2026
- Vendor
- javmah
- Product
- WPGSI: Spreadsheet Integration
- Classifications
- CWE-862, T1565.001, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Feb 25, 2026CVE publishedPublication date reported by the CVE source.
- Feb 25, 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=* <=3.8.3
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
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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