CVE-2026-72126 (GCVE-0-2026-72126)
Vulnerability from cvelistv5
Published
2026-08-15 05:53
Modified
2026-08-17 05:40
Severity ?
VLAI Severity ?
EPSS score ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
can: isotp: use unconditional synchronize_rcu() in isotp_release()
isotp_notify() unregisters the (RCU) CAN filters via can_rx_unregister()
and clears so->bound without waiting for a grace period. isotp_release()
uses so->bound to decide whether it needs to call synchronize_rcu()
before cancelling so->rxtimer, so when NETDEV_UNREGISTER runs first it
skips that synchronize_rcu() and can cancel the timer while an
in-flight isotp_rcv() is still executing and about to re-arm it via
isotp_send_fc(), leading to a use-after-free timer callback on the
freed socket.
sakisho-bot remarked a problem with rtnl_lock held in isotp_notify(),
therefore make isotp_release() always call synchronize_rcu() before
cancelling the timers, regardless of so->bound. This still closes the
original race (isotp_notify() clearing so->bound without waiting for
in-flight isotp_rcv() callers before isotp_release() cancels the RX
timer) without adding any RCU wait to the netdevice notifier path.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Linux | Linux |
Version: 22bfa94db2ef6900c790884fa9461486516626e9 Version: 14a4696bc3118ba49da28f79280e1d55603aa737 Version: 14a4696bc3118ba49da28f79280e1d55603aa737 Version: 14a4696bc3118ba49da28f79280e1d55603aa737 Version: 14a4696bc3118ba49da28f79280e1d55603aa737 Version: 14a4696bc3118ba49da28f79280e1d55603aa737 Version: 14a4696bc3118ba49da28f79280e1d55603aa737 Version: 14a4696bc3118ba49da28f79280e1d55603aa737 Version: 80c6ddf771df2ef786f28c1ca5919b3f1080091b Version: ebf91625b3e404bd2b4b694c7ee71c1e8f8bd08f Version: 5.10.50 ≤ Version: 5.12.17 ≤ Version: 5.13.2 ≤ |
||
{
"containers": {
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"net/can/isotp.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "945d9894502cd9124f5d676181c542ed2000f7c0",
"status": "affected",
"version": "22bfa94db2ef6900c790884fa9461486516626e9",
"versionType": "git"
},
{
"lessThan": "59672aa4bcd8d32172c1ff6a179583981d6acabc",
"status": "affected",
"version": "14a4696bc3118ba49da28f79280e1d55603aa737",
"versionType": "git"
},
{
"lessThan": "15413a082df69175c2f96aeab4c26fe1ff7cff03",
"status": "affected",
"version": "14a4696bc3118ba49da28f79280e1d55603aa737",
"versionType": "git"
},
{
"lessThan": "6280eda96e0707264849fa7d036fed873c1f8a6d",
"status": "affected",
"version": "14a4696bc3118ba49da28f79280e1d55603aa737",
"versionType": "git"
},
{
"lessThan": "cb6abc584a1bfab107ac003d64948a4aef1730aa",
"status": "affected",
"version": "14a4696bc3118ba49da28f79280e1d55603aa737",
"versionType": "git"
},
{
"lessThan": "b88a511308779c225005d7994b8744561bdbafbc",
"status": "affected",
"version": "14a4696bc3118ba49da28f79280e1d55603aa737",
"versionType": "git"
},
{
"lessThan": "b8278ff605187ef3fa0f2705e93251cce4c4f8ee",
"status": "affected",
"version": "14a4696bc3118ba49da28f79280e1d55603aa737",
"versionType": "git"
},
{
"lessThan": "9b1a02e0d980ac6b0e36a90378f847062f81d7e4",
"status": "affected",
"version": "14a4696bc3118ba49da28f79280e1d55603aa737",
"versionType": "git"
},
{
"status": "affected",
"version": "80c6ddf771df2ef786f28c1ca5919b3f1080091b",
"versionType": "git"
},
{
"status": "affected",
"version": "ebf91625b3e404bd2b4b694c7ee71c1e8f8bd08f",
"versionType": "git"
},
{
"lessThan": "5.10.261",
"status": "affected",
"version": "5.10.50",
"versionType": "semver"
},
{
"lessThan": "5.13",
"status": "affected",
"version": "5.12.17",
"versionType": "semver"
},
{
"lessThan": "5.14",
"status": "affected",
"version": "5.13.2",
"versionType": "semver"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"net/can/isotp.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "5.14"
},
{
"lessThan": "5.14",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"version": "5.10.261",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.212",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"version": "6.1.178",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"version": "6.6.145",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.12.*",
"status": "unaffected",
"version": "6.12.97",
"versionType": "semver"
},
{
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"version": "6.18.40",
"versionType": "semver"
},
{
"lessThanOrEqual": "7.1.*",
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.10.261",
"versionStartIncluding": "5.10.50",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.15.212",
"versionStartIncluding": "5.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.1.178",
"versionStartIncluding": "5.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.6.145",
"versionStartIncluding": "5.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.12.97",
"versionStartIncluding": "5.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "6.18.40",
"versionStartIncluding": "5.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.1.5",
"versionStartIncluding": "5.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "7.2",
"versionStartIncluding": "5.14",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.12.17",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.13.2",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncan: isotp: use unconditional synchronize_rcu() in isotp_release()\n\nisotp_notify() unregisters the (RCU) CAN filters via can_rx_unregister()\nand clears so-\u003ebound without waiting for a grace period. isotp_release()\nuses so-\u003ebound to decide whether it needs to call synchronize_rcu()\nbefore cancelling so-\u003erxtimer, so when NETDEV_UNREGISTER runs first it\nskips that synchronize_rcu() and can cancel the timer while an\nin-flight isotp_rcv() is still executing and about to re-arm it via\nisotp_send_fc(), leading to a use-after-free timer callback on the\nfreed socket.\n\nsakisho-bot remarked a problem with rtnl_lock held in isotp_notify(),\ntherefore make isotp_release() always call synchronize_rcu() before\ncancelling the timers, regardless of so-\u003ebound. This still closes the\noriginal race (isotp_notify() clearing so-\u003ebound without waiting for\nin-flight isotp_rcv() callers before isotp_release() cancels the RX\ntimer) without adding any RCU wait to the netdevice notifier path."
}
],
"metrics": [
{
"cvssV3_1": {
"baseScore": 7.8,
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - The UAF is reached through local AF_CAN CAN_ISOTP socket syscalls (socket/bind/close) racing in-kernel ISO-TP RX; a CAN peer can deliver frames, but exploitation requires a local process to close the socket while NETDEV_UNREGISTER clears so-\u003ebound.\nAC:L - The attacker controls all race sides: ISO-TP RX traffic via a local CAN socket or bus peer, concurrent close() on the ISOTP socket, and NETDEV_UNREGISTER by deleting the bound vcan/CAN interface (e.g., in a user namespace with CAP_NET_ADMIN).\nPR:L - CAN_ISOTP socket create/bind/sendmsg/close paths impose no CAP_NET_ADMIN check; an unprivileged local user with access to a CAN netdev, including a user-namespace vcan they create, can reach the vulnerable release/timer path.\nUI:N - No victim interaction is required once the attacker can execute local code; they can open the ISO-TP socket, drive RX via CAN frames, delete the netdev, and close the socket to race isotp_rcv() against isotp_release().\nS:U - Exploitation corrupts kernel heap memory within the same OS security boundary (standard kernel UAF), not a VM/host or IOMMU sandbox escape.\nC:H - Use-after-free of struct isotp_sock in isotp_rx_timer_handler reads freed memory (so-\u003erx.state, sock fields), enabling heap grooming for arbitrary kernel memory disclosure per conservative UAF scoring guidance.\nI:H - The timer callback performs writes to fields within the freed isotp_sock/socket object, giving attacker-influenced kernel heap corruption that can be developed into arbitrary write or privilege-escalation primitives.\nA:H - Executing isotp_rx_timer_handler on a freed socket can cause kernel oops/panic or fatal memory corruption; the UAF is reliably triggerable with attacker-controlled timing."
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-17T05:40:40.020Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/945d9894502cd9124f5d676181c542ed2000f7c0"
},
{
"url": "https://git.kernel.org/stable/c/59672aa4bcd8d32172c1ff6a179583981d6acabc"
},
{
"url": "https://git.kernel.org/stable/c/15413a082df69175c2f96aeab4c26fe1ff7cff03"
},
{
"url": "https://git.kernel.org/stable/c/6280eda96e0707264849fa7d036fed873c1f8a6d"
},
{
"url": "https://git.kernel.org/stable/c/cb6abc584a1bfab107ac003d64948a4aef1730aa"
},
{
"url": "https://git.kernel.org/stable/c/b88a511308779c225005d7994b8744561bdbafbc"
},
{
"url": "https://git.kernel.org/stable/c/b8278ff605187ef3fa0f2705e93251cce4c4f8ee"
},
{
"url": "https://git.kernel.org/stable/c/9b1a02e0d980ac6b0e36a90378f847062f81d7e4"
}
],
"title": "can: isotp: use unconditional synchronize_rcu() in isotp_release()",
"x_generator": {
"engine": "bippy-1.2.0"
}
}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-72126",
"datePublished": "2026-08-15T05:53:03.642Z",
"dateReserved": "2026-08-09T03:40:39.907Z",
"dateUpdated": "2026-08-17T05:40:40.020Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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