Vulnerability-Lookup

GHSA-9HG7-CP6V-469M

Vulnerability from github – Published: 2026-10-23 15:31 – Updated: 2026-10-23 15:31

Details

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

namespace: unhash a dentry before detaching the mounts on it

unlink(), rmdir() and rename() remove the entry from the filesystem, call detach_mounts() on the entry with the inode locked and then call d_delete() once the inode is unlocked.

The thing is that between detach_mounts() and d_delete() the dentry is still hashed and positive. But after detach_mounts() nothing covers the dentry anymore. A lookup that finds this dentry in the dcache can uncover what the mounts hid.

That's a problem when unlinking files or directories that are mountpoints in other mount namespaces. Everybody who had the underlying entry covered can race the detach_mount() call until d_delete() has run.

The race window isn't all that small. It encompasses namespace_unlock() with a full synchronize_rcu_expedited() grace period and the inode_unlock() of the entry.

In my experiments three walkers that kept trying read an overmounted file in 11938 of the 16140 unlinks that removed its mountpoint from a bind mount of the filesystem within a minute.

Fun fact, d_invalidate() has the same ordering problem but gets it right. It unhashes the dentry first and detaches the mounts afterwards. Let's do the same in __detach_mounts():

A lookup that hasn't found the dentry yet misses it in the dcache and waits for the directory lock that the caller holds until the name is gone for good.
A lockless lookup that found it already fails the mount_lock check while the dentry still counts as a mountpoint and the d_seq check once it doesn't, and retries.

This fixes the lockless path. We still need to fix the reference count lookup in a follow-up patch.

So d_drop() the dentry. The dentry stays positive and held but can't be found anymore. Then proceed with the detach and unlink.

Reproducer:

The reads were counted with the program below, three walkers for 60 s in a VM with 4 CPUs. The race window is stretched with the debug patch pasted here. fs.detach_race_walk_us sleeps in lookup_fast() once it found a mountpoint dentry and before its mounts are crossed. fs.detach_race_unlink_us sleeps in vfs_unlink() between detach_mounts() and d_delete().

// SPDX-License-Identifier: GPL-2.0 /* * unlink_covered: unlink a file that is a mountpoint in a detached copy of * its mount, against lookups that open it through that copy. * * A is a tmpfs with the file f1 (content SECRET_F) and the plain file * MARK_A. A' is an open_tree(OPEN_TREE_CLONE) copy of A with MARK_A bound * on A'/f1, held through an O_PATH fd on its root once the tree fd is * closed. Walkers open f1 through that fd while the driver unlinks A/f1, * where nothing is mounted on it. A walker may read MARK_A or get ENOENT. * A read of SECRET_F is a hit: the name was found after its mount was * gone. The lockless walks use openat2(RESOLVE_CACHED). * * usage: unlink_covered [-t seconds] [-w walkers] */ #ifndef _GNU_SOURCE #define _GNU_SOURCE #endif #include #include #include #include #include #include #include #include #include #include #include #include

#ifndef __NR_open_tree #define __NR_open_tree 428 #endif #ifndef __NR_move_mount #define __NR_move_mount 429 #endif #ifndef __NR_openat2 #define __NR_openat2 437 #endif #ifndef OPEN_TREE_CLONE #define OPEN_TREE_CLONE 1 #endif #ifndef OPEN_TREE_CLOEXEC #define OPEN_TREE_CLOEXEC O_CLOEXEC #endif #ifndef MOVE_MOUNT_F_EMPTY_PATH #define MOVE_MOUNT_F_EMPTY_PATH 0x00000004 #endif

#define WORK "/tmp/uc" #define ADIR WORK "/A"

static int duration = 60, nwalkers = 3; static atomic_int stop, writer_waiting; static pthread_rwlock_t cur_lock = PTHREAD_RWLOCK_INITIALIZER; static int cur_fd = -1; /* the root of A', -1 wh ---truncated---

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{
  "affected": [],
  "aliases": [
    "CVE-2026-98981"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-10-23T13:17:19Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnamespace: unhash a dentry before detaching the mounts on it\n\nunlink(), rmdir() and rename() remove the entry from the filesystem,\ncall detach_mounts() on the entry with the inode locked and then call\nd_delete() once the inode is unlocked.\n\nThe thing is that between detach_mounts() and d_delete() the dentry is\nstill hashed and positive. But after detach_mounts() nothing covers the\ndentry anymore. A lookup that finds this dentry in the dcache can\nuncover what the mounts hid.\n\nThat\u0027s a problem when unlinking files or directories that are\nmountpoints in other mount namespaces. Everybody who had the underlying\nentry covered can race the detach_mount() call until d_delete() has run.\n\nThe race window isn\u0027t all that small. It encompasses namespace_unlock()\nwith a full synchronize_rcu_expedited() grace period and the\ninode_unlock() of the entry.\n\nIn my experiments three walkers that kept trying read an overmounted\nfile in 11938 of the 16140 unlinks that removed its mountpoint from a\nbind mount of the filesystem within a minute.\n\nFun fact, d_invalidate() has the same ordering problem but gets it\nright. It unhashes the dentry first and detaches the mounts afterwards.\nLet\u0027s do the same in __detach_mounts():\n\n- A lookup that hasn\u0027t found the dentry yet misses it in the dcache and\n  waits for the directory lock that the caller holds until the name is\n  gone for good.\n\n- A lockless lookup that found it already fails the mount_lock check\n  while the dentry still counts as a mountpoint and the d_seq check once\n  it doesn\u0027t, and retries.\n\nThis fixes the lockless path. We still need to fix the reference count\nlookup in a follow-up patch.\n\nSo d_drop() the dentry. The dentry stays positive and held but can\u0027t be\nfound anymore. Then proceed with the detach and unlink.\n\nReproducer:\n\nThe reads were counted with the program below, three walkers for 60 s\nin a VM with 4 CPUs. The race window is stretched with the debug patch\npasted here. fs.detach_race_walk_us sleeps in lookup_fast() once it\nfound a mountpoint dentry and before its mounts are crossed.\nfs.detach_race_unlink_us sleeps in vfs_unlink() between detach_mounts()\nand d_delete().\n\n  // SPDX-License-Identifier: GPL-2.0\n  /*\n   * unlink_covered: unlink a file that is a mountpoint in a detached copy of\n   * its mount, against lookups that open it through that copy.\n   *\n   * A is a tmpfs with the file f1 (content SECRET_F) and the plain file\n   * MARK_A. A\u0027 is an open_tree(OPEN_TREE_CLONE) copy of A with MARK_A bound\n   * on A\u0027/f1, held through an O_PATH fd on its root once the tree fd is\n   * closed. Walkers open f1 through that fd while the driver unlinks A/f1,\n   * where nothing is mounted on it. A walker may read MARK_A or get ENOENT.\n   * A read of SECRET_F is a hit: the name was found after its mount was\n   * gone. The lockless walks use openat2(RESOLVE_CACHED).\n   *\n   * usage: unlink_covered [-t seconds] [-w walkers]\n   */\n  #ifndef _GNU_SOURCE\n  #define _GNU_SOURCE\n  #endif\n  #include \u003cerrno.h\u003e\n  #include \u003cfcntl.h\u003e\n  #include \u003cpthread.h\u003e\n  #include \u003cstdatomic.h\u003e\n  #include \u003cstdio.h\u003e\n  #include \u003cstdlib.h\u003e\n  #include \u003cstring.h\u003e\n  #include \u003cunistd.h\u003e\n  #include \u003csys/mount.h\u003e\n  #include \u003csys/stat.h\u003e\n  #include \u003csys/syscall.h\u003e\n  #include \u003clinux/openat2.h\u003e\n\n  #ifndef __NR_open_tree\n  #define __NR_open_tree 428\n  #endif\n  #ifndef __NR_move_mount\n  #define __NR_move_mount 429\n  #endif\n  #ifndef __NR_openat2\n  #define __NR_openat2 437\n  #endif\n  #ifndef OPEN_TREE_CLONE\n  #define OPEN_TREE_CLONE 1\n  #endif\n  #ifndef OPEN_TREE_CLOEXEC\n  #define OPEN_TREE_CLOEXEC O_CLOEXEC\n  #endif\n  #ifndef MOVE_MOUNT_F_EMPTY_PATH\n  #define MOVE_MOUNT_F_EMPTY_PATH 0x00000004\n  #endif\n\n  #define WORK \"/tmp/uc\"\n  #define ADIR WORK \"/A\"\n\n  static int duration = 60, nwalkers = 3;\n  static atomic_int stop, writer_waiting;\n  static pthread_rwlock_t cur_lock = PTHREAD_RWLOCK_INITIALIZER;\n  static int cur_fd = -1;\t\t/* the root of A\u0027, -1 wh\n---truncated---",
  "id": "GHSA-9hg7-cp6v-469m",
  "modified": "2026-10-23T15:31:33Z",
  "published": "2026-10-23T15:31:33Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-98981"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/528b383dc35d1e5caf64ddf5d35f983ae543b0d0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8300de4aa5d09061bfcf2af5b52c0cdba3873185"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8d71bfc9b3fc15d7103e82ea9dc5057541866e46"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d29cd99db3db74cf3447be74d25740981789d461"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/db90eecbde319527aa9480c039d32a0f5fe80574"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

CVE-2026-98981 (GCVE-0-2026-98981)

Vulnerability from cvelistv5 – Published: 2026-10-23 12:19 – Updated: 2026-10-23 12:19

Title

namespace: unhash a dentry before detaching the mounts on it

Summary

In the Linux kernel, the following vulnerability has been resolved: namespace: unhash a dentry before detaching the mounts on it unlink(), rmdir() and rename() remove the entry from the filesystem, call detach_mounts() on the entry with the inode locked and then call d_delete() once the inode is unlocked. The thing is that between detach_mounts() and d_delete() the dentry is still hashed and positive. But after detach_mounts() nothing covers the dentry anymore. A lookup that finds this dentry in the dcache can uncover what the mounts hid. That's a problem when unlinking files or directories that are mountpoints in other mount namespaces. Everybody who had the underlying entry covered can race the detach_mount() call until d_delete() has run. The race window isn't all that small. It encompasses namespace_unlock() with a full synchronize_rcu_expedited() grace period and the inode_unlock() of the entry. In my experiments three walkers that kept trying read an overmounted file in 11938 of the 16140 unlinks that removed its mountpoint from a bind mount of the filesystem within a minute. Fun fact, d_invalidate() has the same ordering problem but gets it right. It unhashes the dentry first and detaches the mounts afterwards. Let's do the same in __detach_mounts(): - A lookup that hasn't found the dentry yet misses it in the dcache and waits for the directory lock that the caller holds until the name is gone for good. - A lockless lookup that found it already fails the mount_lock check while the dentry still counts as a mountpoint and the d_seq check once it doesn't, and retries. This fixes the lockless path. We still need to fix the reference count lookup in a follow-up patch. So d_drop() the dentry. The dentry stays positive and held but can't be found anymore. Then proceed with the detach and unlink. Reproducer: The reads were counted with the program below, three walkers for 60 s in a VM with 4 CPUs. The race window is stretched with the debug patch pasted here. fs.detach_race_walk_us sleeps in lookup_fast() once it found a mountpoint dentry and before its mounts are crossed. fs.detach_race_unlink_us sleeps in vfs_unlink() between detach_mounts() and d_delete(). // SPDX-License-Identifier: GPL-2.0 /* * unlink_covered: unlink a file that is a mountpoint in a detached copy of * its mount, against lookups that open it through that copy. * * A is a tmpfs with the file f1 (content SECRET_F) and the plain file * MARK_A. A' is an open_tree(OPEN_TREE_CLONE) copy of A with MARK_A bound * on A'/f1, held through an O_PATH fd on its root once the tree fd is * closed. Walkers open f1 through that fd while the driver unlinks A/f1, * where nothing is mounted on it. A walker may read MARK_A or get ENOENT. * A read of SECRET_F is a hit: the name was found after its mount was * gone. The lockless walks use openat2(RESOLVE_CACHED). * * usage: unlink_covered [-t seconds] [-w walkers] */ #ifndef _GNU_SOURCE #define _GNU_SOURCE #endif #include <errno.h> #include <fcntl.h> #include <pthread.h> #include <stdatomic.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <sys/mount.h> #include <sys/stat.h> #include <sys/syscall.h> #include <linux/openat2.h> #ifndef __NR_open_tree #define __NR_open_tree 428 #endif #ifndef __NR_move_mount #define __NR_move_mount 429 #endif #ifndef __NR_openat2 #define __NR_openat2 437 #endif #ifndef OPEN_TREE_CLONE #define OPEN_TREE_CLONE 1 #endif #ifndef OPEN_TREE_CLOEXEC #define OPEN_TREE_CLOEXEC O_CLOEXEC #endif #ifndef MOVE_MOUNT_F_EMPTY_PATH #define MOVE_MOUNT_F_EMPTY_PATH 0x00000004 #endif #define WORK "/tmp/uc" #define ADIR WORK "/A" static int duration = 60, nwalkers = 3; static atomic_int stop, writer_waiting; static pthread_rwlock_t cur_lock = PTHREAD_RWLOCK_INITIALIZER; static int cur_fd = -1; /* the root of A', -1 wh ---truncated---

Severity

No CVSS data available.

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 7061 records in the last 180 days details

References

5 references

URL	Tags
https://git.kernel.org/stable/c/db90eecbde319527a…
https://git.kernel.org/stable/c/8d71bfc9b3fc15d71…
https://git.kernel.org/stable/c/d29cd99db3db74cf3…
https://git.kernel.org/stable/c/8300de4aa5d09061b…
https://git.kernel.org/stable/c/528b383dc35d1e5ca…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 8ed936b5671bfb33d89bc60bdcc7cf0470ba52fe , < db90eecbde319527aa9480c039d32a0f5fe80574 (git) Affected: 8ed936b5671bfb33d89bc60bdcc7cf0470ba52fe , < 8d71bfc9b3fc15d7103e82ea9dc5057541866e46 (git) Affected: 8ed936b5671bfb33d89bc60bdcc7cf0470ba52fe , < d29cd99db3db74cf3447be74d25740981789d461 (git) Affected: 8ed936b5671bfb33d89bc60bdcc7cf0470ba52fe , < 8300de4aa5d09061bfcf2af5b52c0cdba3873185 (git) Affected: 8ed936b5671bfb33d89bc60bdcc7cf0470ba52fe , < 528b383dc35d1e5caf64ddf5d35f983ae543b0d0 (git)
Linux	Linux	Affected: 3.18 Unaffected: 0 , < 3.18 (semver) Unaffected: 6.6.160 , ≤ 6.6.* (semver) Unaffected: 6.12.114 , ≤ 6.12.* (semver) Unaffected: 6.18.57 , ≤ 6.18.* (semver) Unaffected: 7.2.11 , ≤ 7.2.* (semver) Unaffected: 7.3 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "fs/namespace.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "db90eecbde319527aa9480c039d32a0f5fe80574",
              "status": "affected",
              "version": "8ed936b5671bfb33d89bc60bdcc7cf0470ba52fe",
              "versionType": "git"
            },
            {
              "lessThan": "8d71bfc9b3fc15d7103e82ea9dc5057541866e46",
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              "versionType": "git"
            },
            {
              "lessThan": "d29cd99db3db74cf3447be74d25740981789d461",
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              "versionType": "git"
            },
            {
              "lessThan": "8300de4aa5d09061bfcf2af5b52c0cdba3873185",
              "status": "affected",
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            {
              "lessThan": "528b383dc35d1e5caf64ddf5d35f983ae543b0d0",
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              "versionType": "git"
            }
          ]
        },
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          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "fs/namespace.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "3.18"
            },
            {
              "lessThan": "3.18",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.160",
              "versionType": "semver"
            },
            {
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              "status": "unaffected",
              "version": "6.12.114",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.57",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.2.*",
              "status": "unaffected",
              "version": "7.2.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.3",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.160",
                  "versionStartIncluding": "3.18",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.114",
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                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.57",
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                },
                {
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                },
                {
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                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
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          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnamespace: unhash a dentry before detaching the mounts on it\n\nunlink(), rmdir() and rename() remove the entry from the filesystem,\ncall detach_mounts() on the entry with the inode locked and then call\nd_delete() once the inode is unlocked.\n\nThe thing is that between detach_mounts() and d_delete() the dentry is\nstill hashed and positive. But after detach_mounts() nothing covers the\ndentry anymore. A lookup that finds this dentry in the dcache can\nuncover what the mounts hid.\n\nThat\u0027s a problem when unlinking files or directories that are\nmountpoints in other mount namespaces. Everybody who had the underlying\nentry covered can race the detach_mount() call until d_delete() has run.\n\nThe race window isn\u0027t all that small. It encompasses namespace_unlock()\nwith a full synchronize_rcu_expedited() grace period and the\ninode_unlock() of the entry.\n\nIn my experiments three walkers that kept trying read an overmounted\nfile in 11938 of the 16140 unlinks that removed its mountpoint from a\nbind mount of the filesystem within a minute.\n\nFun fact, d_invalidate() has the same ordering problem but gets it\nright. It unhashes the dentry first and detaches the mounts afterwards.\nLet\u0027s do the same in __detach_mounts():\n\n- A lookup that hasn\u0027t found the dentry yet misses it in the dcache and\n  waits for the directory lock that the caller holds until the name is\n  gone for good.\n\n- A lockless lookup that found it already fails the mount_lock check\n  while the dentry still counts as a mountpoint and the d_seq check once\n  it doesn\u0027t, and retries.\n\nThis fixes the lockless path. We still need to fix the reference count\nlookup in a follow-up patch.\n\nSo d_drop() the dentry. The dentry stays positive and held but can\u0027t be\nfound anymore. Then proceed with the detach and unlink.\n\nReproducer:\n\nThe reads were counted with the program below, three walkers for 60 s\nin a VM with 4 CPUs. The race window is stretched with the debug patch\npasted here. fs.detach_race_walk_us sleeps in lookup_fast() once it\nfound a mountpoint dentry and before its mounts are crossed.\nfs.detach_race_unlink_us sleeps in vfs_unlink() between detach_mounts()\nand d_delete().\n\n  // SPDX-License-Identifier: GPL-2.0\n  /*\n   * unlink_covered: unlink a file that is a mountpoint in a detached copy of\n   * its mount, against lookups that open it through that copy.\n   *\n   * A is a tmpfs with the file f1 (content SECRET_F) and the plain file\n   * MARK_A. A\u0027 is an open_tree(OPEN_TREE_CLONE) copy of A with MARK_A bound\n   * on A\u0027/f1, held through an O_PATH fd on its root once the tree fd is\n   * closed. Walkers open f1 through that fd while the driver unlinks A/f1,\n   * where nothing is mounted on it. A walker may read MARK_A or get ENOENT.\n   * A read of SECRET_F is a hit: the name was found after its mount was\n   * gone. The lockless walks use openat2(RESOLVE_CACHED).\n   *\n   * usage: unlink_covered [-t seconds] [-w walkers]\n   */\n  #ifndef _GNU_SOURCE\n  #define _GNU_SOURCE\n  #endif\n  #include \u003cerrno.h\u003e\n  #include \u003cfcntl.h\u003e\n  #include \u003cpthread.h\u003e\n  #include \u003cstdatomic.h\u003e\n  #include \u003cstdio.h\u003e\n  #include \u003cstdlib.h\u003e\n  #include \u003cstring.h\u003e\n  #include \u003cunistd.h\u003e\n  #include \u003csys/mount.h\u003e\n  #include \u003csys/stat.h\u003e\n  #include \u003csys/syscall.h\u003e\n  #include \u003clinux/openat2.h\u003e\n\n  #ifndef __NR_open_tree\n  #define __NR_open_tree 428\n  #endif\n  #ifndef __NR_move_mount\n  #define __NR_move_mount 429\n  #endif\n  #ifndef __NR_openat2\n  #define __NR_openat2 437\n  #endif\n  #ifndef OPEN_TREE_CLONE\n  #define OPEN_TREE_CLONE 1\n  #endif\n  #ifndef OPEN_TREE_CLOEXEC\n  #define OPEN_TREE_CLOEXEC O_CLOEXEC\n  #endif\n  #ifndef MOVE_MOUNT_F_EMPTY_PATH\n  #define MOVE_MOUNT_F_EMPTY_PATH 0x00000004\n  #endif\n\n  #define WORK \"/tmp/uc\"\n  #define ADIR WORK \"/A\"\n\n  static int duration = 60, nwalkers = 3;\n  static atomic_int stop, writer_waiting;\n  static pthread_rwlock_t cur_lock = PTHREAD_RWLOCK_INITIALIZER;\n  static int cur_fd = -1;\t\t/* the root of A\u0027, -1 wh\n---truncated---"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-23T12:19:58.507Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/db90eecbde319527aa9480c039d32a0f5fe80574"
        },
        {
          "url": "https://git.kernel.org/stable/c/8d71bfc9b3fc15d7103e82ea9dc5057541866e46"
        },
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          "url": "https://git.kernel.org/stable/c/d29cd99db3db74cf3447be74d25740981789d461"
        },
        {
          "url": "https://git.kernel.org/stable/c/8300de4aa5d09061bfcf2af5b52c0cdba3873185"
        },
        {
          "url": "https://git.kernel.org/stable/c/528b383dc35d1e5caf64ddf5d35f983ae543b0d0"
        }
      ],
      "title": "namespace: unhash a dentry before detaching the mounts on it",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-98981",
    "datePublished": "2026-10-23T12:19:58.507Z",
    "dateReserved": "2026-09-25T10:25:14.384Z",
    "dateUpdated": "2026-10-23T12:19:58.507Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

Order JSON

Publication & reservation Sightings KEV catalogs Other timestamps

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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.

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.

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