Unauthenticated object injection via unsafe text sanitization
Published Aug 13, 2026 · Updated Aug 13, 2026
PHP object injection in Booking Activities 1.18.4 and earlier allows remote attackers to trigger object deserialization without authentication. The plugin's text-field sanitization accepts serialized values instead of rejecting them, creating the object-injection path. A privileged user must perform an action for exploitation to succeed, and the public record does not identify the affected function, input vector, gadget chain, or demonstrated end effect.
Summary
What happened
PHP object injection in Booking Activities 1.18.4 and earlier allows remote attackers to trigger object deserialization without authentication. The plugin's text-field sanitization accepts serialized values instead of rejecting them, creating the object-injection path. A privileged user must perform an action for exploitation to succeed, and the public record does not identify the affected function, input vector, gadget chain, or demonstrated end effect.
The record
- CVE
- CVE-2026-28176
- Published
- Aug 13, 2026
- Updated
- Aug 13, 2026
- Vendor
- Booking Activities Team
- Product
- Booking Activities
- Classifications
- CWE-502, CAPEC-586
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 13, 2026CVE publishedPublication date reported by the CVE source.
- Aug 13, 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=n/a <=1.18.4 changes=[{"at":"1.18.5","status":"unaffected"}]
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.
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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