{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-5398", "assignerOrgId": "63664ac6-956c-4cba-a5d0-f46076e16109", "state": "PUBLISHED", "assignerShortName": "freebsd", "dateReserved": "2026-04-02T01:48:17.131Z", "datePublished": "2026-04-22T02:23:56.767Z", "dateUpdated": "2026-04-22T02:23:56.767Z"}, "containers": {"cna": {"datePublic": "2026-04-21T18:00:00.000Z", "title": "Kernel use-after-free bug in the TIOCNOTTY handler", "references": [{"tags": ["vendor-advisory"], "url": "https://security.freebsd.org/advisories/FreeBSD-SA-26:10.tty.asc"}], "affected": [{"defaultStatus": "unknown", "modules": ["tty"], "product": "FreeBSD", "vendor": "FreeBSD", "versions": [{"status": "affected", "versionType": "release", "version": "15.0-RELEASE", "lessThan": "p6"}, {"status": "affected", "versionType": "release", "version": "14.4-RELEASE", "lessThan": "p2"}, {"status": "affected", "versionType": "release", "version": "14.3-RELEASE", "lessThan": "p11"}, {"status": "affected", "versionType": "release", "version": "13.5-RELEASE", "lessThan": "p12"}]}], "credits": [{"lang": "en", "type": "finder", "value": "Nicholas Carlini using Claude, Anthropic"}], "descriptions": [{"lang": "en", "value": "The implementation of TIOCNOTTY failed to clear a back-pointer from the structure representing the controlling terminal to the calling process' session. If the invoking process then exits, the terminal structure may end up containing a pointer to freed memory.\n\nA malicious process can abuse the dangling pointer to grant itself root privileges."}], "problemTypes": [{"descriptions": [{"cweId": "CWE-416", "description": "CWE-416: Use After Free", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"orgId": "63664ac6-956c-4cba-a5d0-f46076e16109", "shortName": "freebsd", "dateUpdated": "2026-04-22T02:23:56.767Z"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "The implementation of TIOCNOTTY failed to clear a back-pointer from the structure representing the controlling terminal to the calling process' session. If the invoking process then exits, the terminal structure may end up containing a pointer to freed memory.\n\nA malicious process can abuse the dangling pointer to grant itself root privileges."}], "id": "CVE-2026-5398", "lastModified": "2026-04-22T03:16:01.213", "metrics": {}, "published": "2026-04-22T03:16:01.213", "references": [{"source": "secteam@freebsd.org", "url": "https://security.freebsd.org/advisories/FreeBSD-SA-26:10.tty.asc"}], "sourceIdentifier": "secteam@freebsd.org", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-416"}], "source": "secteam@freebsd.org", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[15.0-RELEASE,p6)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[14.4-RELEASE,p2)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[14.3-RELEASE,p11)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[13.5-RELEASE,p12)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "FreeBSD", "source": "cna", "vendor": "FreeBSD"}, "product": "freebsd", "vendor": "freebsd"}], "analysis": {"en": {"generated_at": "2026-04-22T04:20:57.396328+00:00", "value": {"mitigation_remediation": ["Apply the latest FreeBSD security updates that contain the TIOCNOTTY patch.", "Restrict use of the TIOCNOTTY ioctl to privileged users only and disable it for untrusted processes.", "Monitor for abnormal privilege\u2011escalation attempts and audit system processes that gain root privileges."], "summary": {"action": "Immediate Patch", "impact": "Root privilege escalation"}, "threat_synthesis": {"affected_systems": "FreeBSD is the affected vendor. No specific product release or version information is listed in the advisory; the vulnerability applies to all affected FreeBSD releases for which the TIOCNOTTY handler implementation is unpatched.", "description_and_impact": "A use\u2011after\u2011free condition in the FreeBSD TIOCNOTTY handler allows a process that has cleared its controlling terminal to later access a dangling pointer in the terminal structure after the process exits. An attacker can use the freed reference to elevate privileges and gain root access.", "risk_and_exploitability": "The CVSS score is not provided, and EPSS is unavailable, but the vulnerability is known to allow local processes to gain root credentials. Since the attack requires the attacker to invoke the TIOCNOTTY ioctl on a controlling terminal, the likely vector is local access. The CVE is not listed in the CISA KEV catalog, yet it remains a critical privilege\u2011escalation flaw."}}}}, "created": "2026-04-22T03:30:06.536006+00:00", "updated": "2026-04-22T04:30:05.297344+00:00", "vendors": ["freebsd", "freebsd$PRODUCT$freebsd"]}