CVE-2026-104084highCWE-613

CVE-2026-104084: high-severity vulnerability in Smartertools Smartermail

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

Published · Updated

41Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 8.7epss 0.3%
exploitation probability
0.3%top 81% of all CVEs
observed exploitation
nono source reports it
1 public exploit(s)
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.
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
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