{"cve":"CVE-2026-63868","nvd":{"published":"2026-07-19T15:16:53.740","modified":"2026-10-26T16:45:25.820","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: garp: fix unsigned integer underflow in garp_pdu_parse_attr\n\nThe receive-side GARP attribute parser computes dlen with reversed\noperands:\n\n        dlen = sizeof(*ga) - ga->len;\n\nga->len is the on-wire attribute length and includes the GARP attribute\nheader. For normal attributes with data, ga->len is larger than\nsizeof(*ga), so the subtraction underflows in unsigned arithmetic.\n\nThe resulting value is later passed to garp_attr_lookup(), whose length\nargument is u8. After truncation, the parsed data length usually no\nlonger matches the length stored for locally registered attributes, so\nreceived Join/Leave events are ignored. This breaks the GARP receive path\nfor common attributes, such as GVRP VLAN registration attributes.\n\nCompute the data length as the attribute length minus the header length.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-191"],"references":["https://git.kernel.org/stable/c/04e22fefac1af3e32f245e9045382348773b5d59","https://git.kernel.org/stable/c/16e408e607a94b646fb14a2a98422c6877ae4b3c","https://git.kernel.org/stable/c/29f28172afb2ae7b31e9bf3e978396f20b381688","https://git.kernel.org/stable/c/74e02121be1dcc0efcd56ebdf0171d6129105659","https://git.kernel.org/stable/c/973cf7c433d27f4d9556d0b7c332543be7ed7a6e"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-26T17:06:43.011188321+00:00"},"epss":{"cve":"CVE-2026-63868","score":0.00174,"percentile":0.06852,"date":"2026-10-26"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}