net: skbuff: don't leave stale bytes in skb_copy_and_csum_bits()
In the Linux kernel, the following vulnerability has been resolved: net: skbuff: don't leave stale bytes in skb_copy_and_csum_bits() When skb_copy_and_csum_bits() reaches unreadable frags it returns 0 after copying only the linear part, and the rest of the caller's buffer is left as it was. The callers copy into a buffer that is about to go out on the wire: an ICMP error quoting the offending packet, or a driver's TX bounce buffer in skb_copy_and_csum_dev(). Neither buffer is zeroed beforehand, so whatever was in memory there gets sent. Zero the part of the buffer we didn't fill. The checksum usually won't match the data any more, so the receiver will usually drop the packet, but either way it no longer carries anything it shouldn't. Only zero for a positive @len, a negative one from a broken caller must not turn into a huge memset().
CVE-2026-99030
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-2026-99030
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": "65249feb6b3df9e17bab5911ee56fa7b0971e231",
"lessThan": "5f19b9cfff79508e8cb09be40d014cb0807f3854",
"versionType": "git"
},
{
"status": "affected",
"version": "65249feb6b3df9e17bab5911ee56fa7b0971e231",
"lessThan": "5551399751e2c9f31e4f3428040985a07e79d9c2",
"versionType": "git"
},
{
"status": "affected",
"version": "65249feb6b3df9e17bab5911ee56fa7b0971e231",
"lessThan": "39d1a6b601831237c6038b5e3ac8dbb883c1700a",
"versionType": "git"
},
{
"status": "affected",
"version": "65249feb6b3df9e17bab5911ee56fa7b0971e231",
"lessThan": "ab9414ed70bd783e902a85c350620dee269bcb2b",
"versionType": "git"
}
],
"programFiles": [
"net/core/skbuff.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.12"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.12",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.12.113",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.57",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.11",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/core/skbuff.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-99030
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #55736 · Revision 1
- Added to Heist Feed
- Publisher date