Vulnerability-Lookup

CVE-2026-64459 (GCVE-0-2026-64459)

Vulnerability from cvelistv5 – Published: 2026-07-25 08:51 – Updated: 2026-07-25 08:51

Title

tcp: restore RCU grace period in tcp_ao_destroy_sock

Summary

In the Linux kernel, the following vulnerability has been resolved: tcp: restore RCU grace period in tcp_ao_destroy_sock Commit 51e547e8c89c ("tcp: Free TCP-AO/TCP-MD5 info/keys without RCU") removed the call_rcu() callback from tcp_ao_destroy_sock(), arguing that "the destruction of info/keys is delayed until the socket destructor" and therefore "no one can discover it anymore". That argument does not hold for the call site in tcp_connect() (net/ipv4/tcp_output.c:4327-4332). At that point the socket is in TCP_SYN_SENT, has already been inserted into the inet ehash by inet_hash_connect() in tcp_v4_connect(), and is therefore very much discoverable: any softirq running tcp_v4_rcv() on another CPU can take the socket out of the ehash, walk into tcp_inbound_hash(), and load tp->ao_info via implicit RCU before bh_lock_sock_nested() is taken on the destroying CPU. The reader path then enters __tcp_ao_do_lookup() (net/ipv4/tcp_ao.c:208) which re-loads tp->ao_info via rcu_dereference_check(); the re-load can still observe the (about-to-be-freed) pointer because there is no synchronize_rcu() between rcu_assign_pointer(tp->ao_info, NULL) and tcp_ao_info_free() in tcp_ao_destroy_sock(). The captured pointer is then walked at line 223: hlist_for_each_entry_rcu(key, &ao->head, node, ...) The writer's synchronous kfree() is free to complete between the line 218 re-fetch and the line 223 hlist iteration. The slab is reused (or simply LIST_POISON1-stamped if not yet reused) and the iteration walks attacker-controlled or poison memory in softirq context. Reproducer (no debug shim, stock x86_64 v7.1-rc2 SMP+KASAN, QEMU+KVM): an unprivileged uid=1000 process inside CLONE_NEWUSER|CLONE_NEWNET installs TCP_MD5SIG + TCP_AO_ADD_KEY on a TCP socket, sprays forged TCP-AO segments toward its eventual 4-tuple via raw sockets, then calls connect(). The md5-wins reconciliation in tcp_connect() fires tcp_ao_destroy_sock(); the softirq backlog reader on the loopback NAPI path crashes on the freed ao->head.first walk: Oops: general protection fault, probably for non-canonical address 0xfbd59c000000002f KASAN: maybe wild-memory-access in range [0xdead000000000178-0xdead00000000017f] CPU: 0 UID: 1000 PID: 100 Comm: repro_userns RIP: 0010:__tcp_ao_do_lookup+0x107/0x1c0 Call Trace: <IRQ> __tcp_ao_do_lookup+0x107/0x1c0 tcp_ao_inbound_lookup.constprop.0+0x12a/0x200 tcp_inbound_ao_hash+0x5ea/0x1520 tcp_inbound_hash+0x7ce/0x1240 tcp_v4_rcv+0x1e7a/0x3e10 ... Restore the RCU grace period: re-add struct rcu_head to tcp_ao_info and replace the synchronous tcp_ao_info_free() with a call_rcu() callback. Readers that captured tp->ao_info before rcu_assign_pointer NULLed it now see the object remain valid until rcu_read_unlock(). With the patch applied the reproducer runs cleanly for 2000 iterations on the same kernel build.

Severity

No CVSS data available.

Assigner

Linux

References

3 references

URL	Tags
https://git.kernel.org/stable/c/657646c08c94ef7b9…
https://git.kernel.org/stable/c/4caf12c778fed3dc3…
https://git.kernel.org/stable/c/8bc4d43bccbd60efe…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 51e547e8c89c661f6fbede4a28b1d33b13625683 , < 657646c08c94ef7b9dbe468fe7828032216f9841 (git) Affected: 51e547e8c89c661f6fbede4a28b1d33b13625683 , < 4caf12c778fed3dc3824cf36263be5e2c491fbd0 (git) Affected: 51e547e8c89c661f6fbede4a28b1d33b13625683 , < 8bc4d43bccbd60efe85d0a44d5bf41762f2f0c30 (git)
Linux	Linux	Affected: 6.18 Unaffected: 0 , < 6.18 (semver) Unaffected: 6.18.39 , ≤ 6.18.* (semver) Unaffected: 7.1.4 , ≤ 7.1.* (semver) Unaffected: 7.2-rc2 , ≤ * (original_commit_for_fix)

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JSON

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          "vendor": "Linux",
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              "operator": "OR"
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: restore RCU grace period in tcp_ao_destroy_sock\n\nCommit 51e547e8c89c (\"tcp: Free TCP-AO/TCP-MD5 info/keys without RCU\")\nremoved the call_rcu() callback from tcp_ao_destroy_sock(), arguing that\n\"the destruction of info/keys is delayed until the socket destructor\"\nand therefore \"no one can discover it anymore\".\n\nThat argument does not hold for the call site in tcp_connect()\n(net/ipv4/tcp_output.c:4327-4332). At that point the socket is in\nTCP_SYN_SENT, has already been inserted into the inet ehash by\ninet_hash_connect() in tcp_v4_connect(), and is therefore very much\ndiscoverable: any softirq running tcp_v4_rcv() on another CPU can take\nthe socket out of the ehash, walk into tcp_inbound_hash(), and load\ntp-\u003eao_info via implicit RCU before bh_lock_sock_nested() is taken on\nthe destroying CPU.\n\nThe reader path then enters __tcp_ao_do_lookup() (net/ipv4/tcp_ao.c:208)\nwhich re-loads tp-\u003eao_info via rcu_dereference_check(); the re-load can\nstill observe the (about-to-be-freed) pointer because there is no\nsynchronize_rcu() between rcu_assign_pointer(tp-\u003eao_info, NULL) and\ntcp_ao_info_free() in tcp_ao_destroy_sock(). The captured pointer is\nthen walked at line 223:\n\n\thlist_for_each_entry_rcu(key, \u0026ao-\u003ehead, node, ...)\n\nThe writer\u0027s synchronous kfree() is free to complete between the line\n218 re-fetch and the line 223 hlist iteration. The slab is reused\n(or simply LIST_POISON1-stamped if not yet reused) and the iteration\nwalks attacker-controlled or poison memory in softirq context.\n\nReproducer (no debug shim, stock x86_64 v7.1-rc2 SMP+KASAN, QEMU+KVM):\nan unprivileged uid=1000 process inside CLONE_NEWUSER|CLONE_NEWNET\ninstalls TCP_MD5SIG + TCP_AO_ADD_KEY on a TCP socket, sprays forged\nTCP-AO segments toward its eventual 4-tuple via raw sockets, then\ncalls connect(). The md5-wins reconciliation in tcp_connect() fires\ntcp_ao_destroy_sock(); the softirq backlog reader on the loopback\nNAPI path crashes on the freed ao-\u003ehead.first walk:\n\n  Oops: general protection fault, probably for non-canonical\n    address 0xfbd59c000000002f\n  KASAN: maybe wild-memory-access in range\n    [0xdead000000000178-0xdead00000000017f]\n  CPU: 0 UID: 1000 PID: 100 Comm: repro_userns\n  RIP: 0010:__tcp_ao_do_lookup+0x107/0x1c0\n  Call Trace: \u003cIRQ\u003e\n    __tcp_ao_do_lookup+0x107/0x1c0\n    tcp_ao_inbound_lookup.constprop.0+0x12a/0x200\n    tcp_inbound_ao_hash+0x5ea/0x1520\n    tcp_inbound_hash+0x7ce/0x1240\n    tcp_v4_rcv+0x1e7a/0x3e10\n    ...\n\nRestore the RCU grace period: re-add struct rcu_head to tcp_ao_info\nand replace the synchronous tcp_ao_info_free() with a call_rcu()\ncallback. Readers that captured tp-\u003eao_info before rcu_assign_pointer\nNULLed it now see the object remain valid until rcu_read_unlock().\nWith the patch applied the reproducer runs cleanly for 2000 iterations\non the same kernel build."
        }
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        "dateUpdated": "2026-07-25T08:51:26.879Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
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          "url": "https://git.kernel.org/stable/c/657646c08c94ef7b9dbe468fe7828032216f9841"
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        {
          "url": "https://git.kernel.org/stable/c/4caf12c778fed3dc3824cf36263be5e2c491fbd0"
        },
        {
          "url": "https://git.kernel.org/stable/c/8bc4d43bccbd60efe85d0a44d5bf41762f2f0c30"
        }
      ],
      "title": "tcp: restore RCU grace period in tcp_ao_destroy_sock",
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    "cveId": "CVE-2026-64459",
    "datePublished": "2026-07-25T08:51:26.879Z",
    "dateReserved": "2026-07-19T15:36:31.789Z",
    "dateUpdated": "2026-07-25T08:51:26.879Z",
    "state": "PUBLISHED"
  },
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      "date": "2026-07-25",
      "epss": "0.00206",
      "percentile": "0.10857"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-64459\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-07-25T10:17:31.073\",\"lastModified\":\"2026-07-25T10:17:31.073\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\ntcp: restore RCU grace period in tcp_ao_destroy_sock\\n\\nCommit 51e547e8c89c (\\\"tcp: Free TCP-AO/TCP-MD5 info/keys without RCU\\\")\\nremoved the call_rcu() callback from tcp_ao_destroy_sock(), arguing that\\n\\\"the destruction of info/keys is delayed until the socket destructor\\\"\\nand therefore \\\"no one can discover it anymore\\\".\\n\\nThat argument does not hold for the call site in tcp_connect()\\n(net/ipv4/tcp_output.c:4327-4332). At that point the socket is in\\nTCP_SYN_SENT, has already been inserted into the inet ehash by\\ninet_hash_connect() in tcp_v4_connect(), and is therefore very much\\ndiscoverable: any softirq running tcp_v4_rcv() on another CPU can take\\nthe socket out of the ehash, walk into tcp_inbound_hash(), and load\\ntp-\u003eao_info via implicit RCU before bh_lock_sock_nested() is taken on\\nthe destroying CPU.\\n\\nThe reader path then enters __tcp_ao_do_lookup() (net/ipv4/tcp_ao.c:208)\\nwhich re-loads tp-\u003eao_info via rcu_dereference_check(); the re-load can\\nstill observe the (about-to-be-freed) pointer because there is no\\nsynchronize_rcu() between rcu_assign_pointer(tp-\u003eao_info, NULL) and\\ntcp_ao_info_free() in tcp_ao_destroy_sock(). The captured pointer is\\nthen walked at line 223:\\n\\n\\thlist_for_each_entry_rcu(key, \u0026ao-\u003ehead, node, ...)\\n\\nThe writer\u0027s synchronous kfree() is free to complete between the line\\n218 re-fetch and the line 223 hlist iteration. The slab is reused\\n(or simply LIST_POISON1-stamped if not yet reused) and the iteration\\nwalks attacker-controlled or poison memory in softirq context.\\n\\nReproducer (no debug shim, stock x86_64 v7.1-rc2 SMP+KASAN, QEMU+KVM):\\nan unprivileged uid=1000 process inside CLONE_NEWUSER|CLONE_NEWNET\\ninstalls TCP_MD5SIG + TCP_AO_ADD_KEY on a TCP socket, sprays forged\\nTCP-AO segments toward its eventual 4-tuple via raw sockets, then\\ncalls connect(). The md5-wins reconciliation in tcp_connect() fires\\ntcp_ao_destroy_sock(); the softirq backlog reader on the loopback\\nNAPI path crashes on the freed ao-\u003ehead.first walk:\\n\\n  Oops: general protection fault, probably for non-canonical\\n    address 0xfbd59c000000002f\\n  KASAN: maybe wild-memory-access in range\\n    [0xdead000000000178-0xdead00000000017f]\\n  CPU: 0 UID: 1000 PID: 100 Comm: repro_userns\\n  RIP: 0010:__tcp_ao_do_lookup+0x107/0x1c0\\n  Call Trace: \u003cIRQ\u003e\\n    __tcp_ao_do_lookup+0x107/0x1c0\\n    tcp_ao_inbound_lookup.constprop.0+0x12a/0x200\\n    tcp_inbound_ao_hash+0x5ea/0x1520\\n    tcp_inbound_hash+0x7ce/0x1240\\n    tcp_v4_rcv+0x1e7a/0x3e10\\n    ...\\n\\nRestore the RCU grace period: re-add struct rcu_head to tcp_ao_info\\nand replace the synchronous tcp_ao_info_free() with a call_rcu()\\ncallback. Readers that captured tp-\u003eao_info before rcu_assign_pointer\\nNULLed it now see the object remain valid until rcu_read_unlock().\\nWith the patch applied the reproducer runs cleanly for 2000 iterations\\non the same kernel build.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"include/net/tcp_ao.h\",\"net/ipv4/tcp_ao.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"51e547e8c89c661f6fbede4a28b1d33b13625683\",\"lessThan\":\"657646c08c94ef7b9dbe468fe7828032216f9841\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"51e547e8c89c661f6fbede4a28b1d33b13625683\",\"lessThan\":\"4caf12c778fed3dc3824cf36263be5e2c491fbd0\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"51e547e8c89c661f6fbede4a28b1d33b13625683\",\"lessThan\":\"8bc4d43bccbd60efe85d0a44d5bf41762f2f0c30\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"include/net/tcp_ao.h\",\"net/ipv4/tcp_ao.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"6.18\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"6.18\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.39\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.4\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2-rc2\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/4caf12c778fed3dc3824cf36263be5e2c491fbd0\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/657646c08c94ef7b9dbe468fe7828032216f9841\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/8bc4d43bccbd60efe85d0a44d5bf41762f2f0c30\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "suse_vex": {
      "aggregate_severity": "not set",
      "current_release_date": "2026-07-25T15:58:55Z",
      "cve": "CVE-2026-64459",
      "id": "CVE-2026-64459",
      "initial_release_date": "2026-07-25T15:58:55Z",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-64459",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64459.json",
      "version": "2"
    }
  }
}

GHSA-6HPW-QG6P-Q7XC

Vulnerability from github – Published: 2026-07-25 12:31 – Updated: 2026-07-25 12:31

Details

In the Linux kernel, the following vulnerability has been resolved:

tcp: restore RCU grace period in tcp_ao_destroy_sock

Commit 51e547e8c89c ("tcp: Free TCP-AO/TCP-MD5 info/keys without RCU") removed the call_rcu() callback from tcp_ao_destroy_sock(), arguing that "the destruction of info/keys is delayed until the socket destructor" and therefore "no one can discover it anymore".

That argument does not hold for the call site in tcp_connect() (net/ipv4/tcp_output.c:4327-4332). At that point the socket is in TCP_SYN_SENT, has already been inserted into the inet ehash by inet_hash_connect() in tcp_v4_connect(), and is therefore very much discoverable: any softirq running tcp_v4_rcv() on another CPU can take the socket out of the ehash, walk into tcp_inbound_hash(), and load tp->ao_info via implicit RCU before bh_lock_sock_nested() is taken on the destroying CPU.

The reader path then enters __tcp_ao_do_lookup() (net/ipv4/tcp_ao.c:208) which re-loads tp->ao_info via rcu_dereference_check(); the re-load can still observe the (about-to-be-freed) pointer because there is no synchronize_rcu() between rcu_assign_pointer(tp->ao_info, NULL) and tcp_ao_info_free() in tcp_ao_destroy_sock(). The captured pointer is then walked at line 223:

hlist_for_each_entry_rcu(key, &ao->head, node, ...)

The writer's synchronous kfree() is free to complete between the line 218 re-fetch and the line 223 hlist iteration. The slab is reused (or simply LIST_POISON1-stamped if not yet reused) and the iteration walks attacker-controlled or poison memory in softirq context.

Reproducer (no debug shim, stock x86_64 v7.1-rc2 SMP+KASAN, QEMU+KVM): an unprivileged uid=1000 process inside CLONE_NEWUSER|CLONE_NEWNET installs TCP_MD5SIG + TCP_AO_ADD_KEY on a TCP socket, sprays forged TCP-AO segments toward its eventual 4-tuple via raw sockets, then calls connect(). The md5-wins reconciliation in tcp_connect() fires tcp_ao_destroy_sock(); the softirq backlog reader on the loopback NAPI path crashes on the freed ao->head.first walk:

Oops: general protection fault, probably for non-canonical address 0xfbd59c000000002f KASAN: maybe wild-memory-access in range [0xdead000000000178-0xdead00000000017f] CPU: 0 UID: 1000 PID: 100 Comm: repro_userns RIP: 0010:__tcp_ao_do_lookup+0x107/0x1c0 Call Trace: __tcp_ao_do_lookup+0x107/0x1c0 tcp_ao_inbound_lookup.constprop.0+0x12a/0x200 tcp_inbound_ao_hash+0x5ea/0x1520 tcp_inbound_hash+0x7ce/0x1240 tcp_v4_rcv+0x1e7a/0x3e10 ...

Restore the RCU grace period: re-add struct rcu_head to tcp_ao_info and replace the synchronous tcp_ao_info_free() with a call_rcu() callback. Readers that captured tp->ao_info before rcu_assign_pointer NULLed it now see the object remain valid until rcu_read_unlock(). With the patch applied the reproducer runs cleanly for 2000 iterations on the same kernel build.

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-64459"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-25T10:17:31Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: restore RCU grace period in tcp_ao_destroy_sock\n\nCommit 51e547e8c89c (\"tcp: Free TCP-AO/TCP-MD5 info/keys without RCU\")\nremoved the call_rcu() callback from tcp_ao_destroy_sock(), arguing that\n\"the destruction of info/keys is delayed until the socket destructor\"\nand therefore \"no one can discover it anymore\".\n\nThat argument does not hold for the call site in tcp_connect()\n(net/ipv4/tcp_output.c:4327-4332). At that point the socket is in\nTCP_SYN_SENT, has already been inserted into the inet ehash by\ninet_hash_connect() in tcp_v4_connect(), and is therefore very much\ndiscoverable: any softirq running tcp_v4_rcv() on another CPU can take\nthe socket out of the ehash, walk into tcp_inbound_hash(), and load\ntp-\u003eao_info via implicit RCU before bh_lock_sock_nested() is taken on\nthe destroying CPU.\n\nThe reader path then enters __tcp_ao_do_lookup() (net/ipv4/tcp_ao.c:208)\nwhich re-loads tp-\u003eao_info via rcu_dereference_check(); the re-load can\nstill observe the (about-to-be-freed) pointer because there is no\nsynchronize_rcu() between rcu_assign_pointer(tp-\u003eao_info, NULL) and\ntcp_ao_info_free() in tcp_ao_destroy_sock(). The captured pointer is\nthen walked at line 223:\n\n\thlist_for_each_entry_rcu(key, \u0026ao-\u003ehead, node, ...)\n\nThe writer\u0027s synchronous kfree() is free to complete between the line\n218 re-fetch and the line 223 hlist iteration. The slab is reused\n(or simply LIST_POISON1-stamped if not yet reused) and the iteration\nwalks attacker-controlled or poison memory in softirq context.\n\nReproducer (no debug shim, stock x86_64 v7.1-rc2 SMP+KASAN, QEMU+KVM):\nan unprivileged uid=1000 process inside CLONE_NEWUSER|CLONE_NEWNET\ninstalls TCP_MD5SIG + TCP_AO_ADD_KEY on a TCP socket, sprays forged\nTCP-AO segments toward its eventual 4-tuple via raw sockets, then\ncalls connect(). The md5-wins reconciliation in tcp_connect() fires\ntcp_ao_destroy_sock(); the softirq backlog reader on the loopback\nNAPI path crashes on the freed ao-\u003ehead.first walk:\n\n  Oops: general protection fault, probably for non-canonical\n    address 0xfbd59c000000002f\n  KASAN: maybe wild-memory-access in range\n    [0xdead000000000178-0xdead00000000017f]\n  CPU: 0 UID: 1000 PID: 100 Comm: repro_userns\n  RIP: 0010:__tcp_ao_do_lookup+0x107/0x1c0\n  Call Trace: \u003cIRQ\u003e\n    __tcp_ao_do_lookup+0x107/0x1c0\n    tcp_ao_inbound_lookup.constprop.0+0x12a/0x200\n    tcp_inbound_ao_hash+0x5ea/0x1520\n    tcp_inbound_hash+0x7ce/0x1240\n    tcp_v4_rcv+0x1e7a/0x3e10\n    ...\n\nRestore the RCU grace period: re-add struct rcu_head to tcp_ao_info\nand replace the synchronous tcp_ao_info_free() with a call_rcu()\ncallback. Readers that captured tp-\u003eao_info before rcu_assign_pointer\nNULLed it now see the object remain valid until rcu_read_unlock().\nWith the patch applied the reproducer runs cleanly for 2000 iterations\non the same kernel build.",
  "id": "GHSA-6hpw-qg6p-q7xc",
  "modified": "2026-07-25T12:31:36Z",
  "published": "2026-07-25T12:31:36Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64459"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4caf12c778fed3dc3824cf36263be5e2c491fbd0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/657646c08c94ef7b9dbe468fe7828032216f9841"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8bc4d43bccbd60efe85d0a44d5bf41762f2f0c30"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

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.

Detection rules are retrieved from Rulezet.

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.

Action not permitted

CVE-2026-64459 (GCVE-0-2026-64459)

GHSA-6HPW-QG6P-Q7XC

Tags

Sightings

Nomenclature