SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-32878

Prior to 9.6.0-alpha.20 and 8.6.44, an attacker can bypass the default request keyword denylist protection and the class-level permission for adding fields by sending a crafted request that exploits prototype pollution in the deep copy mechanism.

MEDIUM 5.3EPSS 0.34%

Does this matter?

Lower severity and a low EPSS score (0.34%). Track it; it rarely justifies an emergency change on its own.

Description

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.6.0-alpha.20 and 8.6.44, an attacker can bypass the default request keyword denylist protection and the class-level permission for adding fields by sending a crafted request that exploits prototype pollution in the deep copy mechanism. This allows injecting fields into class schemas that have field addition locked down, and can cause permanent schema type conflicts that cannot be resolved even with the master key. In 9.6.0-alpha.20 and 8.6.44, the vulnerable third-party deep copy library has been replaced with a built-in deep clone mechanism that handles prototype properties safely, allowing the existing denylist check to correctly detect and reject the prohibited keyword. No known workarounds are available.

CVSS 4.0
5.3 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/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/M
EPSS
0.34% probability · 28th percentile
CISA KEV
Not listed
Weakness
CWE-1321
Affected
parseplatform/parse-server
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.