CVE-2026-39912 | BDVDB-2026-326157 Detail
v2boardv2board
Description#
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 login_with_mail_link_enable 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.
Impact#
Per CVSS v3.1: confidentiality impact high, integrity impact high, availability impact none. Attack vector: network.
Weaknesses#
- CWE-201 Insertion of Sensitive Information Into Sent Data
References#
- https://chocapikk.com/posts/2026/xboard-v2board-account-takeover/
- https://github.com/v2board/v2board/pull/981
- https://github.com/cedar2025/Xboard/pull/873
- https://github.com/v2board/v2board/blob/0ca47622a50116d0ddd7ffb316b157afb57d25e8/app/Http/Controllers/Passport/AuthController.php#L71
- https://github.com/cedar2025/Xboard/blob/1fe6531924cc1ec662a88b9ef725afcf78d660bc/app/Services/Auth/MailLinkService.php#L49
- https://github.com/cedar2025/Xboard/blob/1fe6531924cc1ec662a88b9ef725afcf78d660bc/app/Http/Controllers/V1/Passport/AuthController.php#L51
- https://github.com/cedar2025/Xboard/commit/121511523f04882ec0c7447acd9b8ebcb8a47957
- https://www.vulncheck.com/advisories/v2board-xboard-authentication-token-exposure-via-loginwithmaillink
Exploit#
History#
- Version 1Record published in the CVE List.
- Version 2Most recent update recorded in the CVE List.