net: garp: fix unsigned integer underflow in garp_pdu_parse_attr
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.
CVE-2026-63868
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:CVE-2026-63868
Kernel
Source reference: /affected/1/package/name
- Affected versions
- Not stated in this record
- Fixed versions
- 5.10.259
Source reference:
/affected/1/ranges5.15.210Source reference:
/affected/1/ranges6.1.176Source reference:
/affected/1/ranges6.6.143Source reference:
/affected/1/ranges6.12.94Source reference:
/affected/1/ranges6.18.36Source reference:
/affected/1/ranges7.0.13Source reference:
/affected/1/ranges - Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"ranges": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"type": "GIT",
"events": [
{
"introduced": "eca9ebac651f774d8b10fce7c5d173c3c3d3394f"
},
{
"fixed": "29f28172afb2ae7b31e9bf3e978396f20b381688"
},
{
"fixed": "973cf7c433d27f4d9556d0b7c332543be7ed7a6e"
},
{
"fixed": "d8dcd14aa886b8effd83022c550669f4f262854b"
},
{
"fixed": "74e02121be1dcc0efcd56ebdf0171d6129105659"
},
{
"fixed": "d4c86ea09ae3e63ee5aa86e941fcc38e0e39874a"
},
{
"fixed": "04e22fefac1af3e32f245e9045382348773b5d59"
},
{
"fixed": "a11f1a671b1361f0f1278dc0041374f2730df73f"
},
{
"fixed": "16e408e607a94b646fb14a2a98422c6877ae4b3c"
}
]
}
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63868.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "2.6.27"
},
{
"fixed": "5.10.259"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "5.11.0"
},
{
"fixed": "5.15.210"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "5.16.0"
},
{
"fixed": "6.1.176"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.2.0"
},
{
"fixed": "6.6.143"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.7.0"
},
{
"fixed": "6.12.94"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.13.0"
},
{
"fixed": "6.18.36"
}
]
},
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "6.19.0"
},
{
"fixed": "7.0.13"
}
]
}
],
"package": {
"name": "Kernel",
"ecosystem": "Linux"
},
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63868.json"
}
}
]- Related CVEs
- CVE-2026-63868
Source reference:
/id
Publisher severity
No explicit severity was provided.
- Event
- #50835 · Revision 1
- Added to Heist Feed
- Publisher date