Description
Parse Server before 8.6.103 and 9.0.0 before 9.10.5-alpha.4 contains an information disclosure vulnerability in LiveQuery. Its subscription hash omits constraints next to a $or operator, including the _Session owner filter and beforeSubscribe constraints, so distinct subscriptions are grouped together. Authenticated clients subscribing with $or queries can receive other users' events, including session tokens usable for impersonation.
References2
Metrics
- CVSS 4.0
-
6.0
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 22 · as of 8 November 2026
- CWE
- CWE-200
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