CVE-2026-34595 | Parse Server: LiveQuery protected-field guard bypass via array-like logical operator value

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.70 and 9.7.0-alpha.18, an authenticated user with find class-level permission can bypass the protectedFields class-level permission setting on LiveQuery subscriptions. By sending a subscription with a $or, $and, or $nor operator value as a plain object with numeric keys and a length property (an "array-like" object) instead of an array, the protected-field guard is bypassed. The subscription event firing acts as a binary oracle, allowing the attacker to infer whether a protected field matches a given test value. This issue has been patched in versions 8.6.70 and 9.7.0-alpha.18.

Published: 2026-03-31 Last update: 2026-04-02 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-34595 is rated Low Risk (27.1/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.25%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-34595

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.04% 0.25% +0.21%
2 2026-04-01 — 0.04% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-34595

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 4.0 MEDIUM
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/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:L)
Limited 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]
4.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/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:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 1.4 [email protected]

Weakness enumeration for CVE-2026-34595

GitHub Security Advisory for CVE-2026-34595

GHSA-mmg8-87c5-jrc2 · Severity: medium · Ecosystem: npm — Parse Server has a LiveQuery protected-field guard bypass via array-like logical operator value

Affected software / configurations for CVE-2026-34595

Vendor Product Version Raw CPE
parseplatform parse-server < 8.6.70 cpe:2.3:a:parseplatform:parse-server:*:*:*:*:*:node.js:*:*
parseplatform parse-server >= 9.0.0, < 9.7.0 cpe:2.3:a:parseplatform:parse-server:*:*:*:*:*:node.js:*:*
parseplatform parse-server 9.7.0 cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha1:*:*:*:node.js:*:*
parseplatform parse-server 9.7.0 cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha10:*:*:*:node.js:*:*
parseplatform parse-server 9.7.0 cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha11:*:*:*:node.js:*:*
parseplatform parse-server 9.7.0 cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha12:*:*:*:node.js:*:*
parseplatform parse-server 9.7.0 cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha13:*:*:*:node.js:*:*
parseplatform parse-server 9.7.0 cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha14:*:*:*:node.js:*:*
parseplatform parse-server 9.7.0 cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha15:*:*:*:node.js:*:*
parseplatform parse-server 9.7.0 cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha2:*:*:*:node.js:*:*
parseplatform parse-server 9.7.0 cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha3:*:*:*:node.js:*:*
parseplatform parse-server 9.7.0 cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha4:*:*:*:node.js:*:*
parseplatform parse-server 9.7.0 cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha5:*:*:*:node.js:*:*
parseplatform parse-server 9.7.0 cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha6:*:*:*:node.js:*:*
parseplatform parse-server 9.7.0 cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha7:*:*:*:node.js:*:*
parseplatform parse-server 9.7.0 cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha8:*:*:*:node.js:*:*
parseplatform parse-server 9.7.0 cpe:2.3:a:parseplatform:parse-server:9.7.0:alpha9:*:*:*:node.js:*:*

References for CVE-2026-34595

cvelogic Threat Intelligence