PHP object injection via unsuppressible __pclass class inference in command monitoring events

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

Deserialization of untrusted data in the command monitoring support of the MongoDB PHP Driver can cause class names embedded in document content to be honored when the driver builds monitoring event objects. When an application registers a command monitoring subscriber and includes untrusted data in a database operation, an unauthenticated party who controls that data may cause an application class implementing the driver's persistable interface to be instantiated and its unserialization method invoked with the supplied data. The resulting impact depends on the classes available in the application.

Source published

24 Sep 2026 15:51:16 UTC

Source modified

24 Sep 2026 18:18:09 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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CVSS 4.0 · 6.3 CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N

CVSS 3.1 · 5.6 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L