{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-83742", "assignerOrgId": "50d2cd11-d01a-48ed-9441-5bfce9d63b27", "state": "PUBLISHED", "assignerShortName": "wolfSSL", "dateReserved": "2026-08-31T22:49:43.798Z", "datePublished": "2026-10-07T02:41:48.911Z", "dateUpdated": "2026-10-07T11:30:28.937Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "50d2cd11-d01a-48ed-9441-5bfce9d63b27", "shortName": "wolfSSL", "dateUpdated": "2026-10-07T02:41:48.911Z"}, "title": "wstrncat() unsigned integer underflow leads to an off-by-one null write in wolfSSH on non-Windows platforms", "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-191", "description": "CWE-191 Integer Underflow (Wrap or Wraparound)", "type": "CWE"}]}, {"descriptions": [{"lang": "en", "cweId": "CWE-121", "description": "CWE-121 Stack-based Buffer Overflow", "type": "CWE"}]}, {"descriptions": [{"lang": "en", "cweId": "CWE-193", "description": "CWE-193 Off-by-one Error", "type": "CWE"}]}], "impacts": [{"descriptions": [{"lang": "en", "value": "Write of a single out-of-bounds null byte immediately past the end of a stack buffer in the SFTP path handlers, which may corrupt an adjacent stack value and cause the server process to misbehave or crash. Requires an authenticated SFTP session. The copied path data itself stays within the buffer, and no out-of-bounds read or information disclosure results, because the out-of-bounds null terminates the string. 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{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[1.4.11,1.5.0]"}}], "enrichment": {"confidence": 95.0, "confidence_source": "inferred", "scores": [{"score": 95.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "wolfSSH", "source": "cna", "vendor": "wolfSSL Inc."}, "product": "wolfssh", "vendor": "wolfssl"}], "created": "2026-10-07T04:30:11.961710+00:00", "updated": "2026-10-07T04:45:11.984087+00:00", "vendors": ["wolfssl", "wolfssl$PRODUCT$wolfssh"]}