CVE-2026-63948 (GCVE-0-2026-63948)
Vulnerability from cvelistv5 – Published: 2026-07-19 14:55 – Updated: 2026-07-19 14:55
VLAI
EPSS
VEX
Title
Bluetooth: L2CAP: fix chan ref leak in l2cap_chan_timeout() on !conn
Summary
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: fix chan ref leak in l2cap_chan_timeout() on !conn
__set_chan_timer() takes a l2cap_chan reference via l2cap_chan_hold()
before scheduling the delayed work. The normal path in
l2cap_chan_timeout() drops this reference with l2cap_chan_put() at the
end, but the early return when chan->conn is NULL skips the put,
leaking the reference.
Add the missing l2cap_chan_put() before the early return.
Severity
No CVSS data available.
Assigner
References
8 references
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
06acb75e7ed600d0bbf7bff5628aa8f24a97978c , < 50f1bcaaaa3a80bb1c3472044bc146e8d49d51ee
(git)
Affected: e97e16433eb4533083b096a3824b93a5ca3aee79 , < b5c59a5b469e2a809a2d57eda4ded94235971060 (git) Affected: 8960ff650aec70485b40771cd8e6e8c4cb467d33 , < 8894c2010435a56ce7c6c2a8785860c13554df2f (git) Affected: 955b5b6c54d95b5e7444dfc81c95c8e013f27ac0 , < 63cd225cc13d782a85e2a73c04d0d350153eada1 (git) Affected: adf0398cee86643b8eacde95f17d073d022f782c , < 107c826e4ef9ec5ad8f60e6fe64d8d5325ba508f (git) Affected: adf0398cee86643b8eacde95f17d073d022f782c , < e8a5baff5be273ca07771fd2b9bb1f2a4152917b (git) Affected: adf0398cee86643b8eacde95f17d073d022f782c , < 08d81fe96f80a8e20c7acb573b6a45d901fcf2cd (git) Affected: adf0398cee86643b8eacde95f17d073d022f782c , < 9dbd84990394c51f5cee1e8871bb5ff8af5ed939 (git) Affected: e137e2ba96e51902dc2878131823a96bf8e638ae (git) Affected: 6466ee65e5b27161c846c73ef407f49dfa1bd1d9 (git) Affected: eb86f955488c39526534211f2610e48a5cf8ead4 (git) Affected: 5.10.217 , < 5.10.259 (semver) Affected: 5.15.159 , < 5.15.210 (semver) Affected: 6.1.91 , < 6.1.176 (semver) Affected: 6.6.31 , < 6.6.143 (semver) Affected: 4.19.314 , < 4.20 (semver) Affected: 5.4.276 , < 5.5 (semver) Affected: 6.8.10 , < 6.9 (semver) |
guessed | |
| Linux | Linux |
Affected:
6.9
Unaffected: 0 , < 6.9 (semver) Unaffected: 5.10.259 , ≤ 5.10.* (semver) Unaffected: 5.15.210 , ≤ 5.15.* (semver) Unaffected: 6.1.176 , ≤ 6.1.* (semver) Unaffected: 6.6.143 , ≤ 6.6.* (semver) Unaffected: 6.12.93 , ≤ 6.12.* (semver) Unaffected: 6.18.35 , ≤ 6.18.* (semver) Unaffected: 7.0.12 , ≤ 7.0.* (semver) Unaffected: 7.1 , ≤ * (original_commit_for_fix) |
guessed |
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"net/bluetooth/l2cap_core.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "50f1bcaaaa3a80bb1c3472044bc146e8d49d51ee",
"status": "affected",
"version": "06acb75e7ed600d0bbf7bff5628aa8f24a97978c",
"versionType": "git"
},
{
"lessThan": "b5c59a5b469e2a809a2d57eda4ded94235971060",
"status": "affected",
"version": "e97e16433eb4533083b096a3824b93a5ca3aee79",
"versionType": "git"
},
{
"lessThan": "8894c2010435a56ce7c6c2a8785860c13554df2f",
"status": "affected",
"version": "8960ff650aec70485b40771cd8e6e8c4cb467d33",
"versionType": "git"
},
{
"lessThan": "63cd225cc13d782a85e2a73c04d0d350153eada1",
"status": "affected",
"version": "955b5b6c54d95b5e7444dfc81c95c8e013f27ac0",
"versionType": "git"
},
{
"lessThan": "107c826e4ef9ec5ad8f60e6fe64d8d5325ba508f",
"status": "affected",
"version": "adf0398cee86643b8eacde95f17d073d022f782c",
"versionType": "git"
},
{
"lessThan": "e8a5baff5be273ca07771fd2b9bb1f2a4152917b",
"status": "affected",
"version": "adf0398cee86643b8eacde95f17d073d022f782c",
"versionType": "git"
},
{
"lessThan": "08d81fe96f80a8e20c7acb573b6a45d901fcf2cd",
"status": "affected",
"version": "adf0398cee86643b8eacde95f17d073d022f782c",
"versionType": "git"
},
{
"lessThan": "9dbd84990394c51f5cee1e8871bb5ff8af5ed939",
"status": "affected",
"version": "adf0398cee86643b8eacde95f17d073d022f782c",
"versionType": "git"
},
{
"status": "affected",
"version": "e137e2ba96e51902dc2878131823a96bf8e638ae",
"versionType": "git"
},
{
"status": "affected",
"version": "6466ee65e5b27161c846c73ef407f49dfa1bd1d9",
"versionType": "git"
},
{
"status": "affected",
"version": "eb86f955488c39526534211f2610e48a5cf8ead4",
"versionType": "git"
},
{
"lessThan": "5.10.259",
"status": "affected",
"version": "5.10.217",
"versionType": "semver"
},
{
"lessThan": "5.15.210",
"status": "affected",
"version": "5.15.159",
"versionType": "semver"
},
{
"lessThan": "6.1.176",
"status": "affected",
"version": "6.1.91",
"versionType": "semver"
},
{
"lessThan": "6.6.143",
"status": "affected",
"version": "6.6.31",
"versionType": "semver"
},
{
"lessThan": "4.20",
"status": "affected",
"version": "4.19.314",
"versionType": "semver"
},
{
"lessThan": "5.5",
"status": "affected",
"version": "5.4.276",
"versionType": "semver"
},
{
"lessThan": "6.9",
"status": "affected",
"version": "6.8.10",
"versionType": "semver"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"net/bluetooth/l2cap_core.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "6.9"
},
{
"lessThan": "6.9",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"version": "5.10.259",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.210",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"version": "6.1.176",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"version": "6.6.143",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.93",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.35",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.0.*",
"status": "unaffected",
"version": "7.0.12",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.10.259",
"versionStartIncluding": "5.10.217",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.15.210",
"versionStartIncluding": "5.15.159",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.1.176",
"versionStartIncluding": "6.1.91",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.6.143",
"versionStartIncluding": "6.6.31",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.12.93",
"versionStartIncluding": "6.9",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.18.35",
"versionStartIncluding": "6.9",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.0.12",
"versionStartIncluding": "6.9",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.1",
"versionStartIncluding": "6.9",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "4.19.314",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.4.276",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "6.8.10",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: fix chan ref leak in l2cap_chan_timeout() on !conn\n\n__set_chan_timer() takes a l2cap_chan reference via l2cap_chan_hold()\nbefore scheduling the delayed work. The normal path in\nl2cap_chan_timeout() drops this reference with l2cap_chan_put() at the\nend, but the early return when chan-\u003econn is NULL skips the put,\nleaking the reference.\n\nAdd the missing l2cap_chan_put() before the early return."
}
],
"providerMetadata": {
"dateUpdated": "2026-07-19T14:55:41.985Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/50f1bcaaaa3a80bb1c3472044bc146e8d49d51ee"
},
{
"url": "https://git.kernel.org/stable/c/b5c59a5b469e2a809a2d57eda4ded94235971060"
},
{
"url": "https://git.kernel.org/stable/c/8894c2010435a56ce7c6c2a8785860c13554df2f"
},
{
"url": "https://git.kernel.org/stable/c/63cd225cc13d782a85e2a73c04d0d350153eada1"
},
{
"url": "https://git.kernel.org/stable/c/107c826e4ef9ec5ad8f60e6fe64d8d5325ba508f"
},
{
"url": "https://git.kernel.org/stable/c/e8a5baff5be273ca07771fd2b9bb1f2a4152917b"
},
{
"url": "https://git.kernel.org/stable/c/08d81fe96f80a8e20c7acb573b6a45d901fcf2cd"
},
{
"url": "https://git.kernel.org/stable/c/9dbd84990394c51f5cee1e8871bb5ff8af5ed939"
}
],
"title": "Bluetooth: L2CAP: fix chan ref leak in l2cap_chan_timeout() on !conn",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-63948",
"datePublished": "2026-07-19T14:55:41.985Z",
"dateReserved": "2026-07-19T07:54:57.023Z",
"dateUpdated": "2026-07-19T14:55:41.985Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-63948",
"date": "2026-10-01",
"epss": "0.0022",
"percentile": "0.11286"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"net/bluetooth/l2cap_core.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "50f1bcaaaa3a80bb1c3472044bc146e8d49d51ee",
"status": "affected",
"version": "06acb75e7ed600d0bbf7bff5628aa8f24a97978c",
"versionType": "git"
},
{
"lessThan": "b5c59a5b469e2a809a2d57eda4ded94235971060",
"status": "affected",
"version": "e97e16433eb4533083b096a3824b93a5ca3aee79",
"versionType": "git"
},
{
"lessThan": "8894c2010435a56ce7c6c2a8785860c13554df2f",
"status": "affected",
"version": "8960ff650aec70485b40771cd8e6e8c4cb467d33",
"versionType": "git"
},
{
"lessThan": "63cd225cc13d782a85e2a73c04d0d350153eada1",
"status": "affected",
"version": "955b5b6c54d95b5e7444dfc81c95c8e013f27ac0",
"versionType": "git"
},
{
"lessThan": "107c826e4ef9ec5ad8f60e6fe64d8d5325ba508f",
"status": "affected",
"version": "adf0398cee86643b8eacde95f17d073d022f782c",
"versionType": "git"
},
{
"lessThan": "e8a5baff5be273ca07771fd2b9bb1f2a4152917b",
"status": "affected",
"version": "adf0398cee86643b8eacde95f17d073d022f782c",
"versionType": "git"
},
{
"lessThan": "08d81fe96f80a8e20c7acb573b6a45d901fcf2cd",
"status": "affected",
"version": "adf0398cee86643b8eacde95f17d073d022f782c",
"versionType": "git"
},
{
"lessThan": "9dbd84990394c51f5cee1e8871bb5ff8af5ed939",
"status": "affected",
"version": "adf0398cee86643b8eacde95f17d073d022f782c",
"versionType": "git"
},
{
"status": "affected",
"version": "e137e2ba96e51902dc2878131823a96bf8e638ae",
"versionType": "git"
},
{
"status": "affected",
"version": "6466ee65e5b27161c846c73ef407f49dfa1bd1d9",
"versionType": "git"
},
{
"status": "affected",
"version": "eb86f955488c39526534211f2610e48a5cf8ead4",
"versionType": "git"
},
{
"lessThan": "5.10.259",
"status": "affected",
"version": "5.10.217",
"versionType": "semver"
},
{
"lessThan": "5.15.210",
"status": "affected",
"version": "5.15.159",
"versionType": "semver"
},
{
"lessThan": "6.1.176",
"status": "affected",
"version": "6.1.91",
"versionType": "semver"
},
{
"lessThan": "6.6.143",
"status": "affected",
"version": "6.6.31",
"versionType": "semver"
},
{
"lessThan": "4.20",
"status": "affected",
"version": "4.19.314",
"versionType": "semver"
},
{
"lessThan": "5.5",
"status": "affected",
"version": "5.4.276",
"versionType": "semver"
},
{
"lessThan": "6.9",
"status": "affected",
"version": "6.8.10",
"versionType": "semver"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"net/bluetooth/l2cap_core.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "6.9"
},
{
"lessThan": "6.9",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"version": "5.10.259",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.210",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"version": "6.1.176",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"version": "6.6.143",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.93",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.35",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.0.*",
"status": "unaffected",
"version": "7.0.12",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix"
}
]
}
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: fix chan ref leak in l2cap_chan_timeout() on !conn\n\n__set_chan_timer() takes a l2cap_chan reference via l2cap_chan_hold()\nbefore scheduling the delayed work. The normal path in\nl2cap_chan_timeout() drops this reference with l2cap_chan_put() at the\nend, but the early return when chan-\u003econn is NULL skips the put,\nleaking the reference.\n\nAdd the missing l2cap_chan_put() before the early return."
}
],
"id": "CVE-2026-63948",
"lastModified": "2026-07-27T17:44:23.777",
"metrics": {},
"published": "2026-07-19T16:17:13.460",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/08d81fe96f80a8e20c7acb573b6a45d901fcf2cd"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/107c826e4ef9ec5ad8f60e6fe64d8d5325ba508f"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/50f1bcaaaa3a80bb1c3472044bc146e8d49d51ee"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/63cd225cc13d782a85e2a73c04d0d350153eada1"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/8894c2010435a56ce7c6c2a8785860c13554df2f"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/9dbd84990394c51f5cee1e8871bb5ff8af5ed939"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/b5c59a5b469e2a809a2d57eda4ded94235971060"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/e8a5baff5be273ca07771fd2b9bb1f2a4152917b"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Awaiting Analysis"
}
},
"redhat_vex": {
"aggregate_severity": "Moderate",
"current_release_date": "2026-08-07T13:49:06+00:00",
"cve": "CVE-2026-63948",
"id": "CVE-2026-63948",
"initial_release_date": "2026-07-19T00:00:00+00:00",
"product_status:known_affected": "232",
"product_status:known_not_affected": "42",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: Bluetooth: L2CAP: fix chan ref leak in l2cap_chan_timeout() on !conn",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-63948.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "moderate",
"current_release_date": "2026-10-01T00:47:44Z",
"cve": "CVE-2026-63948",
"id": "CVE-2026-63948",
"initial_release_date": "2026-07-21T13:02:57Z",
"product_status:known_affected": "544",
"product_status:known_not_affected": "208",
"product_status:recommended": "250",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2026-63948",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-63948.json",
"version": "10"
}
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
Loading…