{"id":"CVE-2021-35034","aliases":["EUVD-2021-21681","GHSA-38gc-w4h9-7pmf"],"status":"published","title":"An insufficient session expiration vulnerability in the CGI program of the Zyxel NBG6604 firmware...","description":"An insufficient session expiration vulnerability in the CGI program of the Zyxel NBG6604 firmware could allow a remote attacker to access the device if the correct token can be intercepted.","severity":{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.01079,"percentile":0.65522,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-613"],"published":"2021-12-29T12:36:47Z","modified":"2026-06-17T03:57:01Z","products":[{"vendor":"zyxel","product":"nbg6604 series firmware"},{"vendor":"zyxel","product":"nbg6604_firmware"}],"references":[{"url":"https://www.zyxel.com/support/Zyxel_security_advisory_for_sensitive_information_vulnerabilities_of_NBG6604_home_router.shtml","tags":["x_refsource_CONFIRM","x_transferred","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-35034"},{"url":"https://github.com/advisories/GHSA-38gc-w4h9-7pmf"}],"sources":{"cve":[{"id":"CVE-2021-35034","description":"An insufficient session expiration vulnerability in the CGI program of the Zyxel NBG6604 firmware could allow a remote attacker to access the device if the correct token can be intercepted.","status":"published","published":"2021-12-29T12:36:47Z","modified":"2024-08-04T00:33:49.919Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-613"],"updated_at":"2026-11-02T14:33:09.864034Z"}],"euvd":[{"id":"EUVD-2021-21681","description":"An insufficient session expiration vulnerability in the CGI program of the Zyxel NBG6604 firmware could allow a remote attacker to access the device if the correct token can be intercepted.","status":"published","published":"2021-12-29T12:36:47Z","modified":"2024-08-04T00:33:49Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-03T03:24:31.533826Z"}],"ghsa":[{"id":"GHSA-38gc-w4h9-7pmf","title":"An insufficient session expiration vulnerability in the CGI program of the Zyxel NBG6604 firmware...","description":"An insufficient session expiration vulnerability in the CGI program of the Zyxel NBG6604 firmware could allow a remote attacker to access the device if the correct token can be intercepted.","status":"published","published":"2021-12-30T00:00:23Z","modified":"2023-02-03T05:03:46Z","cwes":["CWE-613"],"updated_at":"2026-11-02T14:53:25.279029Z"}],"nvd":[{"id":"CVE-2021-35034","description":"An insufficient session expiration vulnerability in the CGI program of the Zyxel NBG6604 firmware could allow a remote attacker to access the device if the correct token can be intercepted.","status":"published","published":"2021-12-29T13:15:07.803Z","modified":"2026-06-17T03:57:01.05Z","cvss":[{"version":"3.1","score":7.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","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"},{"version":"2.0","score":6.4,"vector":"AV:N/AC:L/Au:N/C:P/I:P/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-613"],"updated_at":"2026-11-02T14:07:02.977492Z"}]}}