net/iucv: filter frames in afiucv_hs_rcv() by ingress device
In the Linux kernel, the following vulnerability has been resolved: net/iucv: filter frames in afiucv_hs_rcv() by ingress device afiucv_hs_rcv() selects a socket from iucv_sk_list by matching four 8-byte name fields in the transport header alone. No check is made against the net_device the frame arrived on. This can cause a frame arriving on any netdev to be delivered to an AF_IUCV socket. Three problems follow. First, a frame arriving over HiperSockets can be delivered to a socket bound to the classic z/VM IUCV transport, which has iucv->hs_dev == NULL. iucv_sock_bind() takes the classic path whenever the requested userid matches iucv_userid, even on a guest that also has a HiperSockets device carrying the same identifier. The child socket created by afiucv_hs_callback_syn() for such a match inherits hs_dev = NULL and transport = AF_IUCV_TRANS_HIPER, so the first send() on it returns -ENODEV. The socket delivered to accept() is unusable. Second, a frame arriving on one netdev can be delivered to a socket bound to a different IQD device. Which can lead to - Accept-queue exhaustion (DoS) - Attacker-controlled peer identity in the child socket - Data injection into existing sockets - Fabric noise on the IQD fabric, where bogus replies are sent - killing established connections Third, all AF_IUCV sockets live in init_net, as iucv_sock_alloc() calls sk_alloc(&init_net, ...). But even frames arriving on netdev devices in a namespace can be delivered to an IUCV socket. So a process
CVE-2026-81003
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-2026-81003
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": "3881ac441f642d56503818123446f7298442236b",
"lessThan": "639828ad4d374056167391dbaffd13dd5e5e5ddb",
"versionType": "git"
},
{
"status": "affected",
"version": "3881ac441f642d56503818123446f7298442236b",
"lessThan": "92e5c281f1caa287bb58292f2687c9e3ff3aa23e",
"versionType": "git"
},
{
"status": "affected",
"version": "3881ac441f642d56503818123446f7298442236b",
"lessThan": "712330f8a4293cfd97b0d62b7c7dc01862a16b98",
"versionType": "git"
},
{
"status": "affected",
"version": "3881ac441f642d56503818123446f7298442236b",
"lessThan": "0a5af67e7184c6a0e155c317840bd64b37177af4",
"versionType": "git"
},
{
"status": "affected",
"version": "3881ac441f642d56503818123446f7298442236b",
"lessThan": "dfac2936b83be00035ae176f8252e1c1e1de9207",
"versionType": "git"
},
{
"status": "affected",
"version": "3881ac441f642d56503818123446f7298442236b",
"lessThan": "8e3763f1ccac3fc395f9af2b87114c023ced8a3f",
"versionType": "git"
},
{
"status": "affected",
"version": "3881ac441f642d56503818123446f7298442236b",
"lessThan": "a7f0130a091724e69827ab58e74777a88747e892",
"versionType": "git"
},
{
"status": "affected",
"version": "3881ac441f642d56503818123446f7298442236b",
"lessThan": "80230a18c164a4b5bbc048fe2768b219ac17bc5a",
"versionType": "git"
}
],
"programFiles": [
"net/iucv/af_iucv.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.2"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.2",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.270",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.221",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.188",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.157",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.109",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.50",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.4",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/iucv/af_iucv.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-81003
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #34957 · Revision 1
- Added to Heist Feed
- Publisher date