CVE-2026-55666 (GCVE-0-2026-55666)

Vulnerability from cvelistv5 – Published: 2026-06-24 21:06 – Updated: 2026-06-29 15:34
VLAI
Title
Rocket.Chat: Email Parameter Fallback Leads To Account Takeover Within Apple OAuth
Summary
Rocket.Chat is an open-source, secure, fully customizable communications platform. Prior to 8.5.1, 8.4.4, 8.3.6, 8.2.6, 8.1.6, 8.0.7, and 7.10.13, in apps/meteor/app/apple/server/loginHandler.ts, handleIdentityToken parses a JWT issued by Apple during the OAuth flow. The try block checks for an email parameter. If the JWT does not contain an email address, the application falls back to accepting an arbitrary email value supplied directly in the request. Attackers are able to forge Apple JWTs that do not contain an email address and leverage this vulnerability to carry out account takeover attacks. This vulnerability is fixed in 8.5.1, 8.4.4, 8.3.6, 8.2.6, 8.1.6, 8.0.7, and 7.10.13.
Severity
9.3 (Critical)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-26 03:55 UTC
CWE
  • CWE-287 - Improper Authentication
  • CWE-288 - Authentication Bypass Using an Alternate Path or Channel
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7820 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
RocketChat Rocket.Chat Affected: >= 8.5.0-rc.0, < 8.5.1
Affected: >= 8.4.0-rc.0, < 8.4.4
Affected: >= 8.3.0-rc.0, < 8.3.6
Affected: >= 8.2.0-rc.0, < 8.2.6
Affected: >= 8.1.0-rc.0, < 8.1.6
Affected: >= 7.11.0-rc.0, < 8.0.7
Affected: < 7.10.13
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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