User-data modification via hashtag token bypass
Published May 17, 2026 · Updated May 17, 2026
Cross-site request forgery in Bylancer Zechat 1.5 allows attackers to change user information through a crafted form. The form handler accepts an encoded payload in the hashtag parameter and processes it despite the application's CSRF-token check. Exploitation requires a signed-in user to submit attacker-controlled content, and the resulting request changes data with that user's privileges.
Summary
What happened
Cross-site request forgery in Bylancer Zechat 1.5 allows attackers to change user information through a crafted form. The form handler accepts an encoded payload in the hashtag parameter and processes it despite the application's CSRF-token check. Exploitation requires a signed-in user to submit attacker-controlled content, and the resulting request changes data with that user's privileges.
The record
- CVE
- CVE-2018-25334
- Published
- May 17, 2026
- Updated
- May 17, 2026
- Vendor
- Bylancer
- Product
- Zechat
- Classifications
- CWE-352, T1189
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 17, 2026CVE publishedPublication date reported by the CVE source.
- May 17, 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?
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- Affected versionversion=1.5
What conditions does exploitation require?
What is affected?
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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