CVE-2026-33421 [High] | Security Bypass in Parse-Server

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.53 and 9.6.0-alpha.42, Parse Server's LiveQuery WebSocket interface does not enforce Class-Level Permission (CLP) pointer permissions (readUserFields and pointerFields). Any authenticated user can subscribe to LiveQuery events and receive real-time updates for all objects in classes protected by pointer permissions, regardless of whether the pointer fields on those objects point to the subscribing user. This bypasses the intended read access control, allowing unauthorized access to potentially sensitive data that is correctly restricted via the REST API. This issue has been patched in versions 8.6.53 and 9.6.0-alpha.42.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.01%	0.40%	+0.39%
2	2026-03-25	—	0.01%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.01%

0.40%

+0.39%

2026-03-25

—

0.01%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
7.1	4.0	HIGH	`CVSS:4.0/AV:N/AC:L/AT:N/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` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network. Attack complexity (AC:L) Exploitation conditions are straightforward and stable. Attack requirements (AT:N) No additional preconditions are required beyond normal reachability. Privileges required (PR:L) Low privileges are required. User interaction (UI:N) No user interaction is required. Vulnerable system confidentiality impact (VC:H) High confidentiality impact on the vulnerable system. Vulnerable system integrity impact (VI:N) No integrity impact on the vulnerable system. Vulnerable system availability impact (VA:N) No availability impact on the vulnerable system. Subsequent system confidentiality impact (SC:N) No confidentiality impact on subsequent systems. Subsequent system integrity impact (SI:N) No integrity impact on subsequent systems. Subsequent system availability impact (SA:N) No availability impact on subsequent systems. Exploit maturity (threat) (E:X) Not defined: no reliable threat intelligence; scoring assumes the worst case (equivalent to Attacked). Confidentiality requirement (CR:X) Not defined: insufficient information; scoring treats this like High (worst case). Integrity requirement (IR:X) Not defined: insufficient information; scoring treats this like High (worst case). Availability requirement (AR:X) Not defined: insufficient information; scoring treats this like High (worst case). Modified attack vector (MAV:X) Not defined: scoring uses the Base Attack Vector (AV). Modified attack complexity (MAC:X) Not defined: scoring uses the Base Attack Complexity (AC). Modified attack requirements (MAT:X) Not defined: scoring uses the Base Attack Requirements (AT). Modified privileges required (MPR:X) Not defined: scoring uses the Base Privileges Required (PR). Modified user interaction (MUI:X) Not defined: scoring uses the Base User Interaction (UI). Modified vulnerable system confidentiality impact (MVC:X) Not defined: scoring uses the Base VC metric. Modified vulnerable system integrity impact (MVI:X) Not defined: scoring uses the Base VI metric. Modified vulnerable system availability impact (MVA:X) Not defined: scoring uses the Base VA metric. Modified subsequent system confidentiality impact (MSC:X) Not defined: scoring uses the Base SC metric. Modified subsequent system integrity impact (MSI:X) Not defined: scoring uses the Base SI metric. Modified subsequent system availability impact (MSA:X) Not defined: scoring uses the Base SA metric. Safety (supplemental) (S:X) Not evaluated. Automatable (supplemental) (AU:X) Not evaluated. Recovery (supplemental) (R:X) Not evaluated. Value density (supplemental) (V:X) Not evaluated. Vulnerability response effort (supplemental) (RE:X) Not evaluated. Provider urgency (supplemental) (U:X) Not evaluated.	—	—	[email protected]
6.5	3.1	MEDIUM	`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:N) Service keeps running; no real outage angle.	2.8	3.6	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

7.1

4.0

HIGH

CVSS:4.0/AV:N/AC:L/AT:N/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

Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L): Exploitation conditions are straightforward and stable.
Attack requirements (AT:N): No additional preconditions are required beyond normal reachability.
Privileges required (PR:L): Low privileges are required.
User interaction (UI:N): No user interaction is required.
Vulnerable system confidentiality impact (VC:H): High confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:N): No integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:N): No availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N): No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N): No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N): No availability impact on subsequent systems.
Exploit maturity (threat) (E:X): Not defined: no reliable threat intelligence; scoring assumes the worst case (equivalent to Attacked).
Confidentiality requirement (CR:X): Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X): Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X): Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X): Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X): Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X): Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X): Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X): Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X): Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X): Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X): Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X): Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X): Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X): Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:X): Not evaluated.
Automatable (supplemental) (AU:X): Not evaluated.
Recovery (supplemental) (R:X): Not evaluated.
Value density (supplemental) (V:X): Not evaluated.
Vulnerability response effort (supplemental) (RE:X): Not evaluated.
Provider urgency (supplemental) (U:X): Not evaluated.

—

[email protected]

6.5

3.1

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L): A normal user session is enough; they don’t have to be admin.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:N): Service keeps running; no real outage angle.

2.8

3.6

[email protected]

Affected software / configurations for CVE-2026-33421

Vendor	Product	Version	Raw CPE
parseplatform	parse-server	< 8.6.53	cpe:2.3:a:parseplatform:parse-server::::::node.js::*
parseplatform	parse-server	>= 9.0.0, < 9.6.0	cpe:2.3:a:parseplatform:parse-server::::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha1::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha10::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha11::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha12::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha13::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha14::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha15::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha16::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha17::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha18::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha19::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha2::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha20::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha21::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha22::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha23::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha24::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha25::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha26::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha27::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha28::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha29::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha3::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha30::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha31::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha32::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha33::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha34::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha35::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha36::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha37::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha38::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha39::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha4::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha40::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha41::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha5::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha6::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha7::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha8::::node.js::*
parseplatform	parse-server	9.6.0	cpe:2.3:a:parseplatform:parse-server:9.6.0:alpha9::::node.js::*

References for CVE-2026-33421

URL	Tags
https://github.com/parse-community/parse-server/commit/6c3317aca6eb618ac48f999021ae3ef7766ad1ea	Patch
https://github.com/parse-community/parse-server/commit/976dad109f3fe3fbd0a3a35ef62e7a5d35eb0bee	Patch
https://github.com/parse-community/parse-server/pull/10250	Issue Tracking
https://github.com/parse-community/parse-server/pull/10252	Issue Tracking
https://github.com/parse-community/parse-server/security/advisories/GHSA-fph2-r4qg-9576	Vendor Advisory

URL

CVE-2026-33421 | Parse Server: LiveQuery bypasses CLP pointer permission enforcement

Exploit prediction scoring system (EPSS) score for CVE-2026-33421

Common vulnerability scoring system (CVSS) metrics for CVE-2026-33421

Weakness enumeration for CVE-2026-33421

GitHub Security Advisory for CVE-2026-33421

Affected software / configurations for CVE-2026-33421

References for CVE-2026-33421