CVE-2026-39912
V2Board 1.6.1 through 1.7.4 and Xboard through 0.1.9 expose authentication tokens in HTTP response bodies of the loginWithMailLink endpoint when the loginwithmaillinkenable feature is active. Unauthenticated attackers can POST to the loginWithMailLink endpoint with a known email address to receive the full authentication URL in the response, then exchange the token at the token2Login endpoint to obtain a valid bearer token with complete account access including admin privileges.
Package Versions Affected
Automatically patch vulnerabilities without upgrading
CVSS Version
Related Resources
References
https://github.com/cedar2025/Xboard/blob/1fe6531924cc1ec662a88b9ef725afcf78d660bc/app/Http/Controllers/V1/Passport/AuthController.php#L51, https://github.com/cedar2025/Xboard/blob/1fe6531924cc1ec662a88b9ef725afcf78d660bc/app/Services/Auth/MailLinkService.php#L49, https://github.com/v2board/v2board/blob/0ca47622a50116d0ddd7ffb316b157afb57d25e8/app/Http/Controllers/Passport/AuthController.php#L71, https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39912.json, https://nvd.nist.gov/vuln/detail/CVE-2026-39912, https://www.vulncheck.com/advisories/v2board-xboard-authentication-token-exposure-via-loginwithmaillink, https://github.com/cedar2025/Xboard/pull/873, https://github.com/v2board/v2board/pull/981, https://github.com/cedar2025/Xboard/commit/121511523f04882ec0c7447acd9b8ebcb8a47957, https://github.com/cedar2025/Xboard, https://github.com/v2board/v2board, https://chocapikk.com/posts/2026/xboard-v2board-account-takeover/