Executive Summary
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.67 and 9.7.0-alpha.11, an attacker can bypass Cloud Function validator access controls by appending "prototype.constructor" to the function name in the URL. When a Cloud Function handler is declared using the function keyword and its validator is a plain object or arrow function, the trigger store traversal resolves the handler through its own prototype chain while the validator store fails to mirror this traversal, causing all access control enforcement to be skipped. This allows unauthenticated callers to invoke Cloud Functions that are meant to be protected by validators such as requireUser, requireMaster, or custom validation logic. This issue has been patched in versions 8.6.67 and 9.7.0-alpha.11.
Quantitative Risk Analysis
OsVault Risk Score Methodology
The OsVault composite score is a 5-layer non-linear engine — not a simple weighted average. Each input signal is transformed through mathematically appropriate curves before blending, ensuring that exploitability context overrides raw severity when warranted.
Layer 1 (Technical): CVSS is mapped through a piecewise exponential curve with 4 bands (LOW 0–20, MEDIUM 20–55, HIGH 55–85, CRITICAL 85–100), then multiplied by full CVSS vector decomposition factors for Attack Vector, Complexity, Privileges, and User Interaction.
Layer 2 (Threat): Raw EPSS is passed through a logistic sigmoid (k=40, midpoint=0.05) to maximize discrimination in the decision-relevant range. The result is added to an exploit maturity tier base score (Weaponized: 85, Functional: 55, PoC: 40, Unproven: 18).
Layer 3 (KEV Floor):Any CVE in CISA's catalog receives a hard minimum of 93.0 (Functional) or 97.0 (Weaponized). This ensures confirmed exploitation is never buried by low CVSS scores.
Scores ≥70: patch immediately. 40–69: schedule within current sprint. Below 40: standard maintenance cycle.
Remediation Commands
Commands to update each affected package identified in this advisory. Verify the target release explicitly addresses this CVE in the upstream changelog before deploying to production.
npm install parse-server@latestnpm install parse-server@latestAffected Software Subcomponents
CPE Identifiers
Common Platform Enumeration (CPE) names mapped to this advisory by the National Vulnerability Database.
cpe:2.3:a:parseplatform:parse-server:*:*:*:*:*:node.js:*:* cpe:2.3:a:parseplatform:parse-server:*:*:*:*:*:node.js:*:* cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha1:*:*:*:node.js:*:* cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha10:*:*:*:node.js:*:* cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha2:*:*:*:node.js:*:* cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha3:*:*:*:node.js:*:* cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha4:*:*:*:node.js:*:* cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha5:*:*:*:node.js:*:* cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha6:*:*:*:node.js:*:* cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha7:*:*:*:node.js:*:* cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha8:*:*:*:node.js:*:* cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha9:*:*:*:node.js:*:*