Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: net: garp: fix unsigned integer underflow in garp_pdu_parse_attr The receive-side GARP attribute parser computes dlen with reversed operands: dlen = sizeof(*ga) - ga->len; ga->len is the on-wire attribute length and includes the GARP attribute header. For normal attributes with data, ga->len is larger than sizeof(*ga), so the subtraction underflows in unsigned arithmetic. The resulting value is later passed to garp_attr_lookup(), whose length argument is u8. After truncation, the parsed data length usually no longer matches the length stored for locally registered attributes, so received Join/Leave events are ignored. This breaks the GARP receive path for common attributes, such as GVRP VLAN registration attributes. Compute the data length as the attribute length minus the header length.
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
- https://git.kernel.org/stable/c/a11f1a671b1361f0f1278dc0041374f2730df73f
- https://git.kernel.org/stable/c/d4c86ea09ae3e63ee5aa86e941fcc38e0e39874a
- https://git.kernel.org/stable/c/d8dcd14aa886b8effd83022c550669f4f262854b
FAQ
What is CVE-2026-63868?
CVE-2026-63868 is a documented vulnerability. In the Linux kernel, the following vulnerability has been resolved: net: garp: fix unsigned integer underflow in garp_pdu_parse_attr The receive-side GARP attribute parser computes dlen with reverse...
How severe is CVE-2026-63868?
CVSS scoring is not yet available for CVE-2026-63868. Check NVD for updates.
Is there a patch for CVE-2026-63868?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.