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TI-2026-22158 Aliases CVE-2026-27804GHSA-4q3h-vp4r-prv2

Parse Server: Account takeover via JWT algorithm confusion in Google auth adapter

Priority MEDIUM 47CWE-327Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Information disclosure, Security bypass
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-327 and CWE-345.

Summary

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.3 and 9.1.1-alpha.4, an unauthenticated attacker can forge a Google authentication token with `alg: "none"` to log in as any user linked to a Google account, without knowing their credentials. All deployments with Google authentication enabled are affected. The fix in versions 8.6.3 and 9.1.1-alpha.4 hardcodes the expected `RS256` algorithm instead of trusting the JWT header, and replaces the Google adapter's custom key fetcher with `jwks-rsa` which rejects unknown key IDs. As a workaround, dsable Google authentication until upgrading is possible.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00201 10th percentileScored 2026-11-07
Fix Fixed parse-server (parse-community): 9.3.1-alpha.4, 8.6.3parse-server (npm): 9.3.1-alpha.4, 8.6.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
parse-communityparse-server9.0.0 to before 9.3.1-alpha.4; before 8.6.39.3.1-alpha.4, 8.6.3Patch availableCNA
—parse-server (npm)9.0.0 to before 9.3.1-alpha.49.3.1-alpha.4Patch availableGHSA-4q3h-vp4r-prv2
—parse-server (npm)before 8.6.38.6.3Patch availableGHSA-4q3h-vp4r-prv2
  • parse-server Vendorparse-community Affected 9.0.0 to before 9.3.1-alpha.4; before 8.6.3 Fixed in 9.3.1-alpha.4, 8.6.3 Patch available CNA
  • parse-server (npm) Vendor— Affected 9.0.0 to before 9.3.1-alpha.4 Fixed in 9.3.1-alpha.4 Patch available GHSA-4q3h-vp4r-prv2
  • parse-server (npm) Vendor— Affected before 8.6.3 Fixed in 8.6.3 Patch available GHSA-4q3h-vp4r-prv2

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:parseplatform:parse-server:*:*:*:*:*:node.js:*:*before 8.6.3; 9.0.0 to before 9.3.1Vulnerableparse-community
cpe:2.3:a:parseplatform:parse-server:9.3.1:alpha1:*:*:*:node.js:*:*9.3.1 alpha1Vulnerableparse-community
cpe:2.3:a:parseplatform:parse-server:9.3.1:alpha2:*:*:*:node.js:*:*9.3.1 alpha2Vulnerableparse-community
cpe:2.3:a:parseplatform:parse-server:9.3.1:alpha3:*:*:*:node.js:*:*9.3.1 alpha3Vulnerableparse-community
  • cpe:2.3:a:parseplatform:parse-server:*:*:*:*:*:node.js:*:* Versions before 8.6.3; 9.0.0 to before 9.3.1 Vulnerable ·parse-community
  • cpe:2.3:a:parseplatform:parse-server:9.3.1:alpha1:*:*:*:node.js:*:* Versions 9.3.1 alpha1 Vulnerable ·parse-community
  • cpe:2.3:a:parseplatform:parse-server:9.3.1:alpha2:*:*:*:node.js:*:* Versions 9.3.1 alpha2 Vulnerable ·parse-community
  • cpe:2.3:a:parseplatform:parse-server:9.3.1:alpha3:*:*:*:node.js:*:* Versions 9.3.1 alpha3 Vulnerable ·parse-community

Remediation

  • Fix · CNA parse-server (parse-community) Fixed in 9.3.1-alpha.4, 8.6.3
  • Fix · GHSA-4q3h-vp4r-prv2 parse-server (npm) Fixed in 9.3.1-alpha.4 Advisory →
  • Fix · GHSA-4q3h-vp4r-prv2 parse-server (npm) Fixed in 8.6.3 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-27804
  2. 2026-10-03 Alias added: GHSA-4q3h-vp4r-prv2

References

Patch 3

Advisory 1

Other 3

  • TI-2022-08574 Command Injection in Parse server CVSS 3.1CRITICAL 10.0
  • TI-2024-18136 Parse Server literalizeRegexPart SQL Injection CVSS 3.1CRITICAL 10.0
  • TI-2022-18768 Parse Server vulnerable to Remote Code Execution via prototype pollution in MongoDB BSON parser CVSS 3.1CRITICAL 9.8
  • TI-2024-31550 Parse Server's custom object ID allows to acquire role privileges CVSS 3.1HIGH 8.1
  • TI-2023-18316 Parse Server vulnerable to remote code execution via MongoDB BSON parser through prototype pollution CVSS 3.1CRITICAL 9.8
  • TI-2026-23790 Parse Server session token exfiltration via `redirectClassNameForKey` query parameter CVSS 4.0CRITICAL 9.9
See all 101 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences