Cyber Resilience

CVE-2026-30229

High

Published: 06 March 2026

Published
06 March 2026
Modified
11 March 2026
KEV Added
Patch
CVSS Score v4 8.5 CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/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 Score 0.0039 30.5th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-30229 is a high-severity Incorrect Authorization (CWE-863) vulnerability in Parseplatform Parse-Server. Its CVSS base score is 8.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 30.5th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 AC-3 (Access Enforcement) and AC-6 (Least Privilege).

Deeper analysis

CVE-2026-30229 is a high-severity authorization vulnerability (CWE-863) in Parse Server, an open-source backend platform deployable on any Node.js-compatible infrastructure. In versions prior to 8.6.6 and 9.5.0-alpha.4, the readOnlyMasterKey credential can invoke the POST /loginAs endpoint to generate a valid session token for any user account. This flaw enables a read-only master key to bypass intended restrictions and escalate to full user privileges, compromising confidentiality, integrity, and availability with a CVSS v3.1 base score of 7.2 (AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H). Deployments explicitly using readOnlyMasterKey are vulnerable.

An attacker with access to a readOnlyMasterKey—typically a privileged administrative credential—can exploit this remotely over the network with low complexity and no user interaction. By sending a crafted POST request to /loginAs, they obtain a session token impersonating any target user, granting full read and write access to that user's data across the Parse Server instance. This could lead to data exfiltration, modification, or deletion, depending on the application's data model and user permissions.

The Parse community addressed this in Parse Server versions 8.6.6 and 9.5.0-alpha.4, as detailed in the official release notes and security advisory (GHSA-79wj-8rqv-jvp5). Security practitioners should upgrade immediately if using affected versions and review configurations to ensure readOnlyMasterKey is not exposed or misused, disabling it where possible in favor of more granular permissions.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability details

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.6 and 9.5.0-alpha.4, the readOnlyMasterKey can call POST /loginAs to obtain a valid session token for any user. This…

more

allows a read-only credential to impersonate arbitrary users with full read and write access to their data. Any Parse Server deployment that uses readOnlyMasterKey is affected. This issue has been patched in versions 8.6.6 and 9.5.0-alpha.4.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1078 Valid Accounts Stealth
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
Why these techniques?

Authorization bypass in public-facing Parse Server API allows readOnlyMasterKey holder to escalate privileges and impersonate any valid user via crafted /loginAs request, directly mapping to exploitation for privilege escalation and abuse of valid accounts.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-29182Same product: Parseplatform Parse-Server
CVE-2026-34532Same product: Parseplatform Parse-Server
CVE-2026-30965Same product: Parseplatform Parse-Server
CVE-2026-30947Same product: Parseplatform Parse-Server
CVE-2026-31828Same product: Parseplatform Parse-Server
CVE-2026-30863Same product: Parseplatform Parse-Server
CVE-2026-32248Same product: Parseplatform Parse-Server
CVE-2026-27804Same product: Parseplatform Parse-Server
CVE-2026-30949Same product: Parseplatform Parse-Server
CVE-2026-32242Same product: Parseplatform Parse-Server

Affected Assets

parseplatform
parse-server
9.5.0 · ≤ 8.6.6 · 9.0.0 — 9.4.1

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces authorization policy so that readOnlyMasterKey cannot invoke POST /loginAs or obtain session tokens for arbitrary users.

prevent

Ensures the readOnlyMasterKey is restricted to read-only operations and cannot escalate to full user read/write privileges via loginAs.

prevent

Requires prompt application of the vendor patch (8.6.6 / 9.5.0-alpha.4) that eliminates the authorization flaw in the /loginAs endpoint.

References