{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-39912", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-04-07T20:57:06.209Z", "datePublished": "2026-04-09T18:35:35.569Z", "dateUpdated": "2026-07-14T20:00:18.922Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-07-14T20:00:18.922Z" }, "title": "v2board / Xboard Authentication Token Exposure via loginWithMailLink", "descriptions": [ { "lang": "en", "value": "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.", "supportingMedia": [ { "type": "text/html", "base64": false, "value": "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.
" } ] } ], "affected": [ { "vendor": "v2board", "product": "v2board", "repo": "https://github.com/v2board/v2board", "versions": [ { "status": "affected", "version": "1.6.1", "lessThanOrEqual": "1.7.4", "versionType": "semver" }, { "status": "affected", "version": "bdb10bed32c5f37df2f0872c3cb354e9b7a293bd", "lessThanOrEqual": "0ca47622a50116d0ddd7ffb316b157afb57d25e8", "versionType": "git" } ], "defaultStatus": "unknown", "packageURL": "pkg:github/v2board/v2board" }, { "vendor": "cedar2025", "product": "Xboard", "repo": "https://github.com/cedar2025/Xboard", "versions": [ { "status": "affected", "version": "0", "lessThanOrEqual": "0.1.9", "versionType": "semver" }, { "status": "unaffected", "version": "121511523f04882ec0c7447acd9b8ebcb8a47957", "versionType": "git" } ], "defaultStatus": "unaffected", "packageURL": "pkg:github/cedar2025/Xboard" } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:a:v2board:v2board:*:*:*:*:*:*:*:*", "versionStartIncluding": "1.6.1", "versionEndIncluding": "1.7.4" }, { "vulnerable": true, "criteria": "cpe:2.3:a:v2board:v2board:*:*:*:*:*:*:*:*" } ] } ] } ], "problemTypes": [ { "descriptions": [ { "lang": "en", "cweId": "CWE-201", "description": "CWE-201 Insertion of Sensitive Information Into Sent Data", "type": "CWE" } ] } ], "metrics": [ { "format": "CVSS", "scenarios": [ { "lang": "en", "value": "GENERAL" } ], "cvssV4_0": { "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "subConfidentialityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "subIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subAvailabilityImpact": "NONE", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "version": "4.0", "baseSeverity": "CRITICAL", "baseScore": 9.1, "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N" } }, { "format": "CVSS", "scenarios": [ { "lang": "en", "value": "GENERAL" } ], "cvssV3_1": { "version": "3.1", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "NONE", "baseSeverity": "CRITICAL", "baseScore": 9.1, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N" } } ], "source": { "discovery": "EXTERNAL" }, "references": [ { "url": "https://chocapikk.com/posts/2026/xboard-v2board-account-takeover/", "tags": [ "technical-description", "exploit" ] }, { "url": "https://github.com/v2board/v2board/pull/981", "tags": [ "issue-tracking" ] }, { "url": "https://github.com/cedar2025/Xboard/pull/873", "tags": [ "issue-tracking" ] }, { "url": "https://github.com/v2board/v2board/blob/0ca47622a50116d0ddd7ffb316b157afb57d25e8/app/Http/Controllers/Passport/AuthController.php#L71", "tags": [ "related" ] }, { "url": "https://github.com/cedar2025/Xboard/blob/1fe6531924cc1ec662a88b9ef725afcf78d660bc/app/Services/Auth/MailLinkService.php#L49", "tags": [ "related" ] }, { "url": "https://github.com/cedar2025/Xboard/blob/1fe6531924cc1ec662a88b9ef725afcf78d660bc/app/Http/Controllers/V1/Passport/AuthController.php#L51", "tags": [ "related" ] }, { "url": "https://github.com/cedar2025/Xboard/commit/121511523f04882ec0c7447acd9b8ebcb8a47957", "tags": [ "patch" ] }, { "url": "https://www.vulncheck.com/advisories/v2board-xboard-authentication-token-exposure-via-loginwithmaillink", "tags": [ "third-party-advisory" ] } ], "credits": [ { "lang": "en", "value": "Valentin Lobstein (Chocapikk)", "type": "finder" } ], "x_generator": { "engine": "vulncheck" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2026-04-10T20:16:59.517212Z", "id": "CVE-2026-39912", "options": [ { "Exploitation": "poc" }, { "Automatable": "yes" }, { "Technical Impact": "total" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-04-13T15:38:46.529Z" } } ] } }