Bluetooth: L2CAP: Validate L2CAP_INFO_RSP payload length before access
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Validate L2CAP_INFO_RSP payload length before access l2cap_information_rsp() checks that cmd_len covers the fixed l2cap_info_rsp header (type + result, 4 bytes) but then reads rsp->data without verifying that the payload is present: - L2CAP_IT_FEAT_MASK calls get_unaligned_le32(rsp->data), which reads 4 bytes past the header (needs cmd_len >= 8). - L2CAP_IT_FIXED_CHAN reads rsp->data[0], 1 byte past the header (needs cmd_len >= 5). A truncated L2CAP_INFO_RSP with result == L2CAP_IR_SUCCESS triggers an out-of-bounds read of adjacent skb data. Guard each data access with the required payload length check. If the payload is too short, skip the read and let the state machine complete with safe defaults (feat_mask and remote_fixed_chan remain zero from kzalloc), so the info timer cleanup and l2cap_conn_start() still run and the connection is not stalled.
CVE-2026-31393
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-2026-31393
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": "4e8402a3f884427f9233ba436459c158d1f2e114",
"lessThan": "187e6fe939295be36063a1d91f8bebee04399a8c",
"versionType": "git"
},
{
"status": "affected",
"version": "4e8402a3f884427f9233ba436459c158d1f2e114",
"lessThan": "5229e7d15771eac2b5886bfb1f976aea0c1eec14",
"versionType": "git"
},
{
"status": "affected",
"version": "4e8402a3f884427f9233ba436459c158d1f2e114",
"lessThan": "3b646516cba2ebc4b51a72954903326e7c1e443f",
"versionType": "git"
},
{
"status": "affected",
"version": "4e8402a3f884427f9233ba436459c158d1f2e114",
"lessThan": "807bd1258453c4c83f6ae9dbc1e7b44860ff40d0",
"versionType": "git"
},
{
"status": "affected",
"version": "4e8402a3f884427f9233ba436459c158d1f2e114",
"lessThan": "9aeacde4da0f02d42fd968fd32f245828b230171",
"versionType": "git"
},
{
"status": "affected",
"version": "4e8402a3f884427f9233ba436459c158d1f2e114",
"lessThan": "e7ff754e339e3d5ce29aa9f95352d0186df8fbd9",
"versionType": "git"
},
{
"status": "affected",
"version": "4e8402a3f884427f9233ba436459c158d1f2e114",
"lessThan": "db2872d054e467810078e2b9f440a5b326a601b2",
"versionType": "git"
},
{
"status": "affected",
"version": "4e8402a3f884427f9233ba436459c158d1f2e114",
"lessThan": "dd815e6e3918dc75a49aaabac36e4f024d675101",
"versionType": "git"
}
],
"programFiles": [
"net/bluetooth/l2cap_core.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.24"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.24",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.253",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.203",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.167",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.130",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.78",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.20",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "6.19.10",
"versionType": "semver",
"lessThanOrEqual": "6.19.*"
},
{
"status": "unaffected",
"version": "7.0",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/bluetooth/l2cap_core.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-31393
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #39865 · Revision 1
- Added to Heist Feed
- Publisher date