net/sched: sch_netem: fix out-of-bounds access in packet corruption
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_netem: fix out-of-bounds access in packet corruption In netem_enqueue(), the packet corruption logic uses get_random_u32_below(skb_headlen(skb)) to select an index for modifying skb->data. When an AF_PACKET TX_RING sends fully non-linear packets over an IPIP tunnel, skb_headlen(skb) evaluates to 0. Passing 0 to get_random_u32_below() takes the variable-ceil slow path which returns an unconstrained 32-bit random integer. Using this unconstrained value as an offset into skb->data results in an out-of-bounds memory access. Fix this by verifying skb_headlen(skb) is non-zero before attempting to corrupt the linear data area. Fully non-linear packets will silently bypass the corruption logic.
CVE-2026-31675
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-2026-31675
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": "c865e5d99e25a171e8262fc0f7ba608568633c64",
"lessThan": "a14b56863348686dd0387eea8ce66b85cf455908",
"versionType": "git"
},
{
"status": "affected",
"version": "c865e5d99e25a171e8262fc0f7ba608568633c64",
"lessThan": "13a66ca1e235d4bcd53d12d4c68490cad7f8e46f",
"versionType": "git"
},
{
"status": "affected",
"version": "c865e5d99e25a171e8262fc0f7ba608568633c64",
"lessThan": "3a2999704ac36cfb4041fed3652d26a3373e8d12",
"versionType": "git"
},
{
"status": "affected",
"version": "c865e5d99e25a171e8262fc0f7ba608568633c64",
"lessThan": "4fd258e281fa8bc15e9ce2c7691941537e9258ad",
"versionType": "git"
},
{
"status": "affected",
"version": "c865e5d99e25a171e8262fc0f7ba608568633c64",
"lessThan": "d64cb81dcbd54927515a7f65e5e24affdc73c14b",
"versionType": "git"
}
],
"programFiles": [
"net/sched/sch_netem.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.16"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.16",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.134",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.81",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.22",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "6.19.12",
"versionType": "semver",
"lessThanOrEqual": "6.19.*"
},
{
"status": "unaffected",
"version": "7.0",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/sched/sch_netem.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-31675
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #39948 · Revision 1
- Added to Heist Feed
- Publisher date