{"id":"CVE-2026-107276","aliases":["EUVD-2026-94395","GHSA-fjjq-85mx-vg3v"],"status":"published","title":"MISP Email OTP Race Condition Allows One-Time Password to Be Consumed by Multiple Concurrent Requests","description":"MISP contains a race condition in the email-based one-time password (OTP) login flow. When two HTTP requests carrying the same valid OTP are submitted concurrently, both can successfully authenticate and establish a session. The root cause is that the OTP value is read from the shared store, validated, and then deleted in separate non-atomic steps, allowing a second in-flight request to read the same value before the first request's deletion takes effect.\n\nPreconditions:\n\n- The target MISP instance has email OTP login enabled.\n\n- The attacker possesses a valid, unexpired OTP (e.g., via email interception or social engineering).\n\n- The attacker can issue two HTTP POST requests in close temporal proximity.\n\nImpact:\n\n- The one-time-use guarantee of the OTP is violated; a single code can yield two authenticated sessions.\n\n- This weakens the authentication control and may facilitate unauthorized access if the OTP is shared or intercepted.\n\nAffected versions: \u003c2.5.48","severity":{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00213,"percentile":0.11694,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-362","CWE-367"],"published":"2026-10-07T15:36:49Z","modified":"2026-10-28T02:31:03Z","products":[{"vendor":"misp","product":"misp"}],"references":[{"url":"https://github.com/MISP/MISP/commit/ba95e67d5","tags":["patch","fix"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-107276","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-fjjq-85mx-vg3v"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/107xxx/CVE-2026-107276.json","tags":["advisory"]},{"url":"https://github.com/MISP/MISP","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-107276","title":"MISP Email OTP Race Condition Allows One-Time Password to Be Consumed by Multiple Concurrent Requests","description":"MISP contains a race condition in the email-based one-time password (OTP) login flow. When two HTTP requests carrying the same valid OTP are submitted concurrently, both can successfully authenticate and establish a session. The root cause is that the OTP value is read from the shared store, validated, and then deleted in separate non-atomic steps, allowing a second in-flight request to read the same value before the first request's deletion takes effect.\n\nPreconditions:\n\n- The target MISP instance has email OTP login enabled.\n\n- The attacker possesses a valid, unexpired OTP (e.g., via email interception or social engineering).\n\n- The attacker can issue two HTTP POST requests in close temporal proximity.\n\nImpact:\n\n- The one-time-use guarantee of the OTP is violated; a single code can yield two authenticated sessions.\n\n- This weakens the authentication control and may facilitate unauthorized access if the OTP is shared or intercepted.\n\nAffected versions: \u003c2.5.48","status":"published","published":"2026-10-07T15:36:49.564Z","modified":"2026-10-07T20:28:21.466Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N","level":"medium","assessor":"cna"}],"cwes":["CWE-362","CWE-367"],"updated_at":"2026-11-02T13:45:14.072357Z"}],"euvd":[{"id":"EUVD-2026-94395","description":"MISP contains a race condition in the email-based one-time password (OTP) login flow. When two HTTP requests carrying the same valid OTP are submitted concurrently, both can successfully authenticate and establish a session. The root cause is that the OTP value is read from the shared store, validated, and then deleted in separate non-atomic steps, allowing a second in-flight request to read the same value before the first request's deletion takes effect.\n\nPreconditions:\n\n- The target MISP instance has email OTP login enabled.\n\n- The attacker possesses a valid, unexpired OTP (e.g., via email interception or social engineering).\n\n- The attacker can issue two HTTP POST requests in close temporal proximity.\n\nImpact:\n\n- The one-time-use guarantee of the OTP is violated; a single code can yield two authenticated sessions.\n\n- This weakens the authentication control and may facilitate unauthorized access if the OTP is shared or intercepted.\n\nAffected versions: \u003c2.5.48","status":"published","published":"2026-10-07T15:36:49Z","modified":"2026-10-07T20:28:21Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N","level":"medium"}],"updated_at":"2026-11-02T17:27:33.904651Z"}],"ghsa":[{"id":"GHSA-fjjq-85mx-vg3v","title":"MISP contains a race condition in the email-based one-time password (OTP) login flow. When two...","description":"MISP contains a race condition in the email-based one-time password (OTP) login flow. When two HTTP requests carrying the same valid OTP are submitted concurrently, both can successfully authenticate and establish a session. The root cause is that the OTP value is read from the shared store, validated, and then deleted in separate non-atomic steps, allowing a second in-flight request to read the same value before the first request's deletion takes effect.\n\nPreconditions:\n\n- The target MISP instance has email OTP login enabled.\n\n- The attacker possesses a valid, unexpired OTP (e.g., via email interception or social engineering).\n\n- The attacker can issue two HTTP POST requests in close temporal proximity.\n\nImpact:\n\n- The one-time-use guarantee of the OTP is violated; a single code can yield two authenticated sessions.\n\n- This weakens the authentication control and may facilitate unauthorized access if the OTP is shared or intercepted.\n\nAffected versions: \u003c2.5.48","status":"published","published":"2026-10-07T18:32:09Z","modified":"2026-10-07T18:32:14Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/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":"medium"}],"cwes":["CWE-362"],"updated_at":"2026-11-02T15:12:54.703562Z"}],"nvd":[{"id":"CVE-2026-107276","description":"MISP contains a race condition in the email-based one-time password (OTP) login flow. When two HTTP requests carrying the same valid OTP are submitted concurrently, both can successfully authenticate and establish a session. The root cause is that the OTP value is read from the shared store, validated, and then deleted in separate non-atomic steps, allowing a second in-flight request to read the same value before the first request's deletion takes effect.\n\nPreconditions:\n\n- The target MISP instance has email OTP login enabled.\n\n- The attacker possesses a valid, unexpired OTP (e.g., via email interception or social engineering).\n\n- The attacker can issue two HTTP POST requests in close temporal proximity.\n\nImpact:\n\n- The one-time-use guarantee of the OTP is violated; a single code can yield two authenticated sessions.\n\n- This weakens the authentication control and may facilitate unauthorized access if the OTP is shared or intercepted.\n\nAffected versions: \u003c2.5.48","status":"published","published":"2026-10-07T16:17:47.213Z","modified":"2026-10-07T21:17:14.903Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/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":"medium","assessor":"secondary"}],"cwes":["CWE-362","CWE-367"],"updated_at":"2026-11-02T14:12:54.809359Z"}],"osv":[{"id":"CVE-2026-107276","title":"MISP Email OTP Race Condition Allows One-Time Password to Be Consumed by Multiple Concurrent Requests","description":"MISP contains a race condition in the email-based one-time password (OTP) login flow. When two HTTP requests carrying the same valid OTP are submitted concurrently, both can successfully authenticate and establish a session. The root cause is that the OTP value is read from the shared store, validated, and then deleted in separate non-atomic steps, allowing a second in-flight request to read the same value before the first request's deletion takes effect.\n\nPreconditions:\n\n- The target MISP instance has email OTP login enabled.\n\n- The attacker possesses a valid, unexpired OTP (e.g., via email interception or social engineering).\n\n- The attacker can issue two HTTP POST requests in close temporal proximity.\n\nImpact:\n\n- The one-time-use guarantee of the OTP is violated; a single code can yield two authenticated sessions.\n\n- This weakens the authentication control and may facilitate unauthorized access if the OTP is shared or intercepted.\n\nAffected versions: \u003c2.5.48","status":"published","published":"2026-10-07T15:36:49.564Z","modified":"2026-10-28T02:31:03.71060632Z","cvss":[{"version":"4.0","score":6.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N","level":"medium"}],"cwes":["CWE-362","CWE-367"],"updated_at":"2026-11-02T15:44:54.933106Z"}]}}