What’s Vulnerable › Vulnerabilities

CVE-2021-25294

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 11.3% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2021-01-18 · updated 2026-06-17
• Weakness: CWE-502

Description

OpenCATS through 0.9.5-3 unsafely deserializes index.php?m=activity requests, leading to remote code execution. This occurs because lib/DataGrid.php calls unserialize for the parametersactivity:ActivityDataGrid parameter. The PHP object injection exploit chain can leverage an __destruct magic method in guzzlehttp.

Affected products

• OpenCATS: through 0.9.5-3

References

• https://github.com/snoopysecurity/snoopysecurity.github.io/blob/master/web-application-security/2021/01/16/09_opencats_php_object_injection.html
• https://snoopysecurity.github.io/web-application-security/2021/01/16/09_opencats_php_object_injection.html
• https://www.opencats.org/news/
• https://github.com/snoopysecurity/snoopysecurity.github.io/blob/master/web-application-security/2021/01/16/09_opencats_php_object_injection.html
• https://snoopysecurity.github.io/web-application-security/2021/01/16/09_opencats_php_object_injection.html
• https://www.opencats.org/news/

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