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vuln-cve/data/2026/68xxx/CVE-2026-68341.json
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{
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"cveMetadata": {
"cveId": "CVE-2026-68341",
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"state": "PUBLISHED",
"assignerShortName": "Linux",
"dateReserved": "2026-07-30T09:28:09.384Z",
"datePublished": "2026-08-10T12:03:17.821Z",
"dateUpdated": "2026-08-17T05:03:41.213Z"
},
"containers": {
"cna": {
"providerMetadata": {
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux",
"dateUpdated": "2026-08-17T05:03:41.213Z"
},
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\novpn: fix use after free in unlock_ovpn()\n\nunlock_ovpn() iterates over the release_list using llist_for_each_entry()\nand drops the peer reference inside the loop body via ovpn_peer_put().\n\nIf this drops the last reference, the peer is eventually freed. However,\nllist_for_each_entry() reads peer->release_entry.next in the loop advance\nexpression, which runs after the body. By that time the peer may have\nalready been freed, resulting in a use after free when advancing to the\nnext list entry.\n\nFix this by using llist_for_each_entry_safe(), which caches the next\npointer before executing the loop body."
}
],
"metrics": [
{
"cvssV3_1": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"baseScore": 8.8,
"baseSeverity": "HIGH"
},
"scenarios": [
{
"lang": "en",
"value": "AV:N - unlock_ovpn() is reached directly from remote-peer activity: a malformed/aborted OpenVPN TCP stream schedules ovpn_tcp_peer_del_work() -> ovpn_peer_del() (tcp.c:154/287/506), peer disconnect hits ovpn_tcp_close(), and remote peers falling silent make ovpn_peer_keepalive_work() queue peers onto release_list. No local action is needed to enter the vulnerable loop.\nAC:L - The attacker controls both the trigger and its repetition rate: a remote peer can force transport errors, reconnects and keepalive expiries arbitrarily often, and in MP mode can control how many peers land on release_list at once, plus generate traffic-driven allocation pressure to influence slab reuse of the freed ovpn_peer.\nPR:L - The vulnerable loop only runs for peers already installed in the kernel, which the openvpn userspace daemon does for a connected client, so the attacker acts as an established (low-privileged) VPN peer rather than an unauthenticated stranger; no administrative rights on the target are needed.\nUI:N - Peer removal and the subsequent list walk happen automatically inside the kernel's TCP error/close handling and keepalive worker; no administrator or user action on the victim host is required.\nS:U - The use-after-free corrupts kernel heap state within the same kernel security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The freed ovpn_peer is re-read to obtain the next list pointer, so a reclaimed and re-populated slab object lets the attacker steer the walk onto arbitrary memory that is then dereferenced (peer->sock, peer->refcount), yielding a kernel-memory read primitive and disclosure of sensitive kernel data.\nI:H - Continuing the walk onto a stale/attacker-groomed object causes rcu_replace_pointer() writes, lock_sock() and kref_put() (a controlled decrement plus invocation of a release callback) on a bogus struct ovpn_peer, giving heap-spray-based write and control-flow-hijack potential typical of exploitable UAFs.\nA:H - Dereferencing freed or recycled memory as an ovpn_peer reliably produces oops/panic or slab corruption, taking down the VPN gateway kernel; the path is remotely repeatable, so it is a dependable denial of service."
}
]
}
],
"affected": [
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"drivers/net/ovpn/peer.c"
],
"versions": [
{
"version": "80747caef33d77f5c1b3d24644e6d7dae69066b5",
"lessThan": "5b96227c0e8b212b74838424c929fc889aedb555",
"status": "affected",
"versionType": "git"
},
{
"version": "80747caef33d77f5c1b3d24644e6d7dae69066b5",
"lessThan": "4cdb209f12a89c5faf9be0c45edb90ccdf65db0c",
"status": "affected",
"versionType": "git"
},
{
"version": "80747caef33d77f5c1b3d24644e6d7dae69066b5",
"lessThan": "e1ad6fe5db719874efa45b2caf9934552e09fc43",
"status": "affected",
"versionType": "git"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"drivers/net/ovpn/peer.c"
],
"versions": [
{
"version": "6.16",
"status": "affected"
},
{
"version": "0",
"lessThan": "6.16",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.18.42",
"lessThanOrEqual": "6.18.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "7.1.6",
"lessThanOrEqual": "7.1.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "7.2",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "6.16",
"versionEndExcluding": "6.18.42"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "6.16",
"versionEndExcluding": "7.1.6"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "6.16",
"versionEndExcluding": "7.2"
}
]
}
]
}
],
"references": [
{
"url": "https://git.kernel.org/stable/c/5b96227c0e8b212b74838424c929fc889aedb555"
},
{
"url": "https://git.kernel.org/stable/c/4cdb209f12a89c5faf9be0c45edb90ccdf65db0c"
},
{
"url": "https://git.kernel.org/stable/c/e1ad6fe5db719874efa45b2caf9934552e09fc43"
}
],
"title": "ovpn: fix use after free in unlock_ovpn()",
"x_generator": {
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}