Request-control bypass via ignored Content-Length
Published Dec 15, 2025 · Updated Dec 15, 2025
Client-side request desynchronization in PHPJabbers Member Login Script 3.3 allows remote attackers to bypass request controls. Its POST handler ignores Content-Length without closing the connection, so a request embedded in the body is parsed as the next request. No authentication is required, and a crafted POST can make a secondary request bypass normal server-side request processing.
Summary
What happened
Client-side request desynchronization in PHPJabbers Member Login Script 3.3 allows remote attackers to bypass request controls. Its POST handler ignores Content-Length without closing the connection, so a request embedded in the body is parsed as the next request. No authentication is required, and a crafted POST can make a secondary request bypass normal server-side request processing.
The record
- CVE
- CVE-2023-53878
- Published
- Dec 15, 2025
- Updated
- Dec 15, 2025
- Vendor
- PHPJabbers
- Product
- Member Login Script
- Classifications
- CWE-444, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Dec 15, 2025CVE publishedPublication date reported by the CVE source.
- Dec 15, 2025Record 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=3.3
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
- Member Login Script 3.3 - Client-side desyncproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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