netfilter: nft_fib: reject fib expression on the netdev egress hook
In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_fib: reject fib expression on the netdev egress hook A fib expression in a netdev egress base chain dereferences nft_in(pkt), NULL on the transmit path, causing a NULL pointer dereference at eval. nft_fib_validate() masks the hook with NF_INET_* values, but netdev hook numbers are a separate enum that aliases them (NF_NETDEV_EGRESS == NF_INET_LOCAL_IN), so an egress chain passes validation and then faults. Add nft_fib_netdev_validate() that limits each result/flag to the netdev hook where the device it reads exists: the input-device cases (OIF, OIFNAME, ADDRTYPE with F_IIF) to ingress, the output-device case (ADDRTYPE with F_OIF) to egress, ADDRTYPE with no device flag to both. Also restrict nft_fib_validate() to NFPROTO_IPV4/IPV6/INET so its NF_INET_* masks are not applied to another family's hooks.
CVE-2026-72254
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-2026-72254
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": "42df6e1d221dddc0f2acf2be37e68d553ad65f96",
"lessThan": "4fee43759b489559a491f7c95f9bfa7a1d0c7a10",
"versionType": "git"
},
{
"status": "affected",
"version": "42df6e1d221dddc0f2acf2be37e68d553ad65f96",
"lessThan": "568931f26af4727a51e8521f72efbc78d3b82410",
"versionType": "git"
},
{
"status": "affected",
"version": "42df6e1d221dddc0f2acf2be37e68d553ad65f96",
"lessThan": "d01c913febead04a01a5f3a6374d1f45504dc523",
"versionType": "git"
},
{
"status": "affected",
"version": "42df6e1d221dddc0f2acf2be37e68d553ad65f96",
"lessThan": "f68305267ebda7e839b5e8f77e8d77535a3d5a0f",
"versionType": "git"
},
{
"status": "affected",
"version": "42df6e1d221dddc0f2acf2be37e68d553ad65f96",
"lessThan": "d07955dd34ecae17d35d8c7d0a273a3fba653a8c",
"versionType": "git"
}
],
"programFiles": [
"net/netfilter/nft_fib.c",
"net/netfilter/nft_fib_netdev.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.16"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.16",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.148",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.101",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.42",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/netfilter/nft_fib.c",
"net/netfilter/nft_fib_netdev.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-72254
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #32998 · Revision 1
- Added to Heist Feed
- Publisher date