Vulnerability · CVE-2023-53878
Member Login Script 3.3 contains a client-side desynchronization vulnerability that allows attackers to manipulate HTTP request handling by exploiting Content-Length header parsing
Published Dec 15, 2025 · catalog updated May 12, 2026 · PHPJabbers Member Login Script
Last checked Oct 29, 2026. A connected source was read within the last 7 days.
Check if you run it
No confirmed exploitation is on record for CVE-2023-53878. EPSS is 0.37%. Act only if a listed version of PHPJabbers Member Login Script is installed.
Gaps on this record
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- Medium6.9
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.37%
- Remediation
- Vendor / distro source
- Affected products
- vendor PHPJabbers Member Login Script 3.3
Member Login Script 3.3 contains a client-side desynchronization vulnerability that allows attackers to manipulate HTTP request handling by exploiting Content-Length header parsing. Attackers can send crafted POST requests with smuggled secondary requests to potentially bypass server-side request processing controls.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- vendor PHPJabbers Member Login Script 3.33.3
How to fix CVE-2023-53878
No stored fix
No vendor fix text is stored. Use the linked advisory before you change production.
Version check
Seen in 3.3
Advisory
Open the cve_org record and follow its fix.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2023-53878. EPSS is 0.37%. Act only if a listed version of PHPJabbers Member Login Script is installed.
Which versions are affected?
Compare what you have installed with PHPJabbers Member Login Script 3.3 3.3. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 0.37%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Dec 15, 2025 · EUVD
Detected
Member Login Script 3.3 contains a client-side desynchronization vulnerability that allows attackers to manipulate HTTP request handling by exploiting Content-Length header parsing. Attackers can send crafted POST requests with smuggled secondary requests to potentially bypass server-side request processing controls.
May 12, 2026 · EUVD
Updated
Member Login Script 3.3 contains a client-side desynchronization vulnerability that allows attackers to manipulate HTTP request handling by exploiting Content-Length header parsing. Attackers can send crafted POST requests with smuggled secondary requests to potentially bypass server-side request processing controls.
Sources
- CVE.orgVulnerability recordCVE-2023-53878
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2023-53878
30-day exploitation probability 0.37%
first.org - EUVDVulnerability recordEUVD-2025-203431
Member Login Script 3.3 contains a client-side desynchronization vulnerability that allows attackers to manipulate HTTP request handling by exploiting Content-Length header parsing. Attackers can send crafted POST requests with smuggled secondary requests to potentially bypass se
euvd.enisa.europa.eu
References
Freshness
Last verified in this catalog Oct 29, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.
- FIRST EPSSOct 29, 2026
- CVE.orgOct 26, 2026
- EUVDOct 26, 2026