net: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp()
In the Linux kernel, the following vulnerability has been resolved: net: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp() The commit 4f61f133f354 ("net: tap: NULL pointer derefence in dev_parse_header_protocol when skb->dev is null") fixed a crash in tap_get_user() by assigning skb->dev before calling tun_vnet_hdr_to_skb(). This is required because virtio_net_hdr_to_skb() may invoke dev_parse_header_protocol(), which dereferences skb->dev. Without the assignment, a NULL pointer dereference can occur. However, tap_get_user_xdp() still parses the virtio-net header before assigning skb->dev. When the vhost TX path passes an XDP buffer containing a GSO virtio-net header but the protocol is set to zero on purpose, tun_vnet_hdr_to_skb() can reach dev_parse_header_protocol() while skb->dev is still NULL, resulting in a crash. Fix this by looking up the tap device and assigning skb->dev before calling tun_vnet_hdr_to_skb(), matching the ordering already used in tap_get_user(). Preserve the existing RCU read-side critical section across dev_queue_xmit().
CVE-2026-74684
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: cve:CVE-2026-74684
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "924a9bc362a5223cd448ca08c3dde21235adc310",
"lessThan": "61dd022c55c7307ec119e5672cb141cccbecf3b1",
"versionType": "git"
},
{
"status": "affected",
"version": "924a9bc362a5223cd448ca08c3dde21235adc310",
"lessThan": "15583b07fd691a844fbf7b3ad612cdc9e9a657c0",
"versionType": "git"
},
{
"status": "affected",
"version": "924a9bc362a5223cd448ca08c3dde21235adc310",
"lessThan": "8b444b126cd8e4473e652f529753ed4dd1360a9c",
"versionType": "git"
},
{
"status": "affected",
"version": "924a9bc362a5223cd448ca08c3dde21235adc310",
"lessThan": "164c31ee252ebd1ac8f44c2dfc5486b6d9a0379b",
"versionType": "git"
},
{
"status": "affected",
"version": "924a9bc362a5223cd448ca08c3dde21235adc310",
"lessThan": "3874892dd27d5387aa9a06f58d9060f18f351d24",
"versionType": "git"
},
{
"status": "affected",
"version": "ea3fb2ce5fa794d02135f5c079e05cd6fc3f545d",
"versionType": "git"
},
{
"status": "affected",
"version": "54ef8243c3c8e90f1ea5792e6752e021a25c8eb3",
"versionType": "git"
},
{
"status": "affected",
"version": "ca278267d6cd9544645731732455b6b20cb0e895",
"versionType": "git"
},
{
"status": "affected",
"version": "faa3baa2828c5e1c4374f3e60041f75c64f5fcb6",
"versionType": "git"
},
{
"status": "affected",
"version": "99b1d3f74b9ef72c2f74c8e4c078e1bc0706e748",
"versionType": "git"
},
{
"status": "affected",
"version": "4.14.226",
"lessThan": "4.15",
"versionType": "semver"
},
{
"status": "affected",
"version": "4.19.181",
"lessThan": "4.20",
"versionType": "semver"
},
{
"status": "affected",
"version": "5.4.106",
"lessThan": "5.5",
"versionType": "semver"
},
{
"status": "affected",
"version": "5.10.24",
"lessThan": "5.11",
"versionType": "semver"
},
{
"status": "affected",
"version": "5.11.7",
"lessThan": "5.12",
"versionType": "semver"
}
],
"programFiles": [
"drivers/net/tap.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.12"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.12",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.160",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.105",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.45",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.9",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/net/tap.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-74684
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #46585 · Revision 1
- Added to Heist Feed
- Publisher date