vsock/virtio: fix potential underflow in virtio_transport_get_credit()
In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: fix potential underflow in virtio_transport_get_credit() The credit calculation in virtio_transport_get_credit() uses unsigned arithmetic: ret = vvs->peer_buf_alloc - (vvs->tx_cnt - vvs->peer_fwd_cnt); If the peer shrinks its advertised buffer (peer_buf_alloc) while bytes are in flight, the subtraction can underflow and produce a large positive value, potentially allowing more data to be queued than the peer can handle. Reuse virtio_transport_has_space() which already handles this case and add a comment to make it clear why we are doing that. [Stefano: use virtio_transport_has_space() instead of duplicating the code] [Stefano: tweak the commit message]
CVE-2026-23069
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-2026-23069
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": "06a8fc78367d070720af960dcecec917d3ae5f3b",
"lessThan": "d96de882d6b99955604669d962ae14e94b66a551",
"versionType": "git"
},
{
"status": "affected",
"version": "06a8fc78367d070720af960dcecec917d3ae5f3b",
"lessThan": "02f9af192b98d15883c70dd41ac76d1b0217c899",
"versionType": "git"
},
{
"status": "affected",
"version": "06a8fc78367d070720af960dcecec917d3ae5f3b",
"lessThan": "d05bc313788f0684b27f0f5b60c52a844669b542",
"versionType": "git"
},
{
"status": "affected",
"version": "06a8fc78367d070720af960dcecec917d3ae5f3b",
"lessThan": "ec0f1b3da8061be3173d1c39faaf9504f91942c3",
"versionType": "git"
},
{
"status": "affected",
"version": "06a8fc78367d070720af960dcecec917d3ae5f3b",
"lessThan": "3ef3d52a1a9860d094395c7a3e593f3aa26ff012",
"versionType": "git"
}
],
"programFiles": [
"net/vmw_vsock/virtio_transport_common.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "4.8"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "4.8",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.1.162",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.122",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.68",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.8",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "6.19",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/vmw_vsock/virtio_transport_common.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-23069
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #39738 · Revision 1
- Added to Heist Feed
- Publisher date