{"id":"CVE-2026-40496","aliases":["EUVD-2026-24049","GHSA-2783-wxmm-wmwr"],"status":"published","title":"FreeScout has Predictable Attachment Token that Allows Unauthenticated Private File Download via Brute Force","description":"FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.213, attachment download tokens are generated using a weak and predictable formula: `md5(APP_KEY + attachment_id + size)`. Since attachment_id is sequential and size can be brute-forced in a small range, an unauthenticated attacker can forge valid tokens and download any private attachment without credentials. Version 1.8.213 fixes the issue.","severity":{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:P","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00403,"percentile":0.3492,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-330","CWE-340"],"published":"2026-04-21T01:38:50Z","modified":"2026-10-28T02:30:51Z","products":[{"vendor":"freescout","product":"freescout"},{"vendor":"freescout-help-desk","product":"freescout"}],"references":[{"url":"https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-2783-wxmm-wmwr","tags":["x_refsource_CONFIRM","Exploit","Vendor Advisory","advisory"]},{"url":"https://github.com/freescout-help-desk/freescout/commit/dbdf8f2260b43a21818255c70f0b61b9de9cd555","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/freescout-help-desk/freescout/releases/tag/1.8.213","tags":["x_refsource_MISC","Release Notes","web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40496.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-40496","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-40496","title":"FreeScout has Predictable Attachment Token that Allows Unauthenticated Private File Download via Brute Force","description":"FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.213, attachment download tokens are generated using a weak and predictable formula: `md5(APP_KEY + attachment_id + size)`. Since attachment_id is sequential and size can be brute-forced in a small range, an unauthenticated attacker can forge valid tokens and download any private attachment without credentials. Version 1.8.213 fixes the issue.","status":"published","published":"2026-04-21T01:38:50.117Z","modified":"2026-04-21T13:50:39.454Z","cvss":[{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:P","level":"high","assessor":"cna"}],"cwes":["CWE-330","CWE-340"],"updated_at":"2026-11-02T13:43:11.445168Z"}],"euvd":[{"id":"EUVD-2026-24049","description":"FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.213, attachment download tokens are generated using a weak and predictable formula: `md5(APP_KEY + attachment_id + size)`. Since attachment_id is sequential and size can be brute-forced in a small range, an unauthenticated attacker can forge valid tokens and download any private attachment without credentials. Version 1.8.213 fixes the issue.","status":"published","published":"2026-04-21T01:38:50Z","modified":"2026-04-21T13:50:39Z","cvss":[{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:P","level":"high"}],"updated_at":"2026-11-02T19:24:22.012341Z"}],"nvd":[{"id":"CVE-2026-40496","description":"FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.213, attachment download tokens are generated using a weak and predictable formula: `md5(APP_KEY + attachment_id + size)`. Since attachment_id is sequential and size can be brute-forced in a small range, an unauthenticated attacker can forge valid tokens and download any private attachment without credentials. Version 1.8.213 fixes the issue.","status":"published","published":"2026-04-21T02:16:08.35Z","modified":"2026-06-17T10:45:22.987Z","cvss":[{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical","assessor":"primary"}],"cwes":["CWE-330","CWE-340"],"updated_at":"2026-11-02T14:12:15.120927Z"}],"osv":[{"id":"CVE-2026-40496","title":"FreeScout has Predictable Attachment Token that Allows Unauthenticated Private File Download via Brute Force","description":"FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.213, attachment download tokens are generated using a weak and predictable formula: `md5(APP_KEY + attachment_id + size)`. Since attachment_id is sequential and size can be brute-forced in a small range, an unauthenticated attacker can forge valid tokens and download any private attachment without credentials. Version 1.8.213 fixes the issue.","status":"published","published":"2026-04-21T01:38:50.117Z","modified":"2026-10-28T02:30:51.061861159Z","cvss":[{"version":"4.0","score":8.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:P","level":"high"}],"cwes":["CWE-330","CWE-340"],"updated_at":"2026-11-02T15:45:03.424067Z"}]}}