CVE-2026-104084 PUBLISHED

SmarterMail < Build 9777 Stale JWT Role Claim Privilege Escalation via Refresh Token

Assigner: VulnCheck
Reserved: 01.10.2026 Published: 09.10.2026 Updated: 09.10.2026

SmarterMail before build 9777 contains a privilege escalation vulnerability where JWT access and refresh tokens embed a role claim at issuance that is not revalidated against the account's current role when redeemed through POST /api/v1/auth/refresh-token. Attackers who capture a refresh token issued before an administrator demotion, or a demoted user whose session was not actively polling at the time of demotion, can replay the stale token to obtain a new access token retaining the higher-privilege role (such as DomainAdmin or SysAdmin) until natural token expiry.

Metrics

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CVSS Score: 8.7

Product Status

Vendor Smartertools
Product Smartermail
Versions Default: unaffected
  • affected from 0 to Build 9777 (excl.)

Credits

  • evan finder

References

Problem Types

  • Insufficient Session Expiration CWE