GHSA-GQGJ-WW6J-QXJ3

Vulnerability from github – Published: 2026-09-25 12:31 – Updated: 2026-10-03 12:31
VLAI
Details

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

netfilter: nf_log: unregister loggers before per-net teardown

nf_log_syslog and nfnetlink_log unregister their per-network namespace operations before unregistering their global logger backends. This leaves a window where a sysctl or netlink writer can rebind the still- registered logger after the per-net pre-exit callback cleared the old selection.

The race looks like this:

CPU 0 CPU 1 ---- ---- unregister_pernet_subsys() nf_log_unset(net, logger) net->nf.nf_loggers[pf] = NULL

                                    lock nf_log_mutex
                                    find logger in loggers[][]
                                    net->nf.nf_loggers[pf] = logger
                                    unlock nf_log_mutex

nf_log_unregister(logger) lock nf_log_mutex loggers[pf][type] = NULL unlock nf_log_mutex synchronize_rcu() module exit returns module core frees backend memory

Later, a sysctl read or packet logging operation can dereference the stale per-net logger pointer.

Fix this by unregistering the global logger backends before tearing down per-net state. Once the global registrations are gone, later writers can no longer rebind the logger. unregister_pernet_subsys() already waits for an RCU grace period after the pre-exit callback clears the per-net selection, while nf_log_unregister() continues to cover readers of the global logger table.

Apply this ordering fix to both nf_log backends that combine per-net teardown with global logger registration.

Severity
7.0 (High)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2026-97608"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-25T11:17:14Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_log: unregister loggers before per-net teardown\n\nnf_log_syslog and nfnetlink_log unregister their per-network namespace\noperations before unregistering their global logger backends. This\nleaves a window where a sysctl or netlink writer can rebind the still-\nregistered logger after the per-net pre-exit callback cleared the old\nselection.\n\nThe race looks like this:\n\n  CPU 0                                 CPU 1\n  ----                                  ----\n  unregister_pernet_subsys()\n    nf_log_unset(net, logger)\n      net-\u003enf.nf_loggers[pf] = NULL\n\n                                        lock nf_log_mutex\n                                        find logger in loggers[][]\n                                        net-\u003enf.nf_loggers[pf] = logger\n                                        unlock nf_log_mutex\n\n  nf_log_unregister(logger)\n    lock nf_log_mutex\n    loggers[pf][type] = NULL\n    unlock nf_log_mutex\n    synchronize_rcu()\n  module exit returns\n  module core frees backend memory\n\nLater, a sysctl read or packet logging operation can dereference the\nstale per-net logger pointer.\n\nFix this by unregistering the global logger backends before tearing down\nper-net state. Once the global registrations are gone, later writers can\nno longer rebind the logger. unregister_pernet_subsys() already waits\nfor an RCU grace period after the pre-exit callback clears the per-net\nselection, while nf_log_unregister() continues to cover readers of the\nglobal logger table.\n\nApply this ordering fix to both nf_log backends that combine per-net\nteardown with global logger registration.",
  "id": "GHSA-gqgj-ww6j-qxj3",
  "modified": "2026-10-03T12:31:19Z",
  "published": "2026-09-25T12:31:26Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-97608"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2c018cc4842c33f0c732962e2ab58635e8ae5823"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/51417230716b73f6aa1dc402b3a56d3382a694dc"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/64803ba0a05791cf9ca874466480e4c4cadaf7ab"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/90166834b7dc6131aa42b6b14b8b4ed47be97079"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b0514ca1ee6f2b708d6c602ea946acdfc6a90e24"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/dce24f3a146948595bb1b86347f31e20b4975daa"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/eaec35fae8f2052c1878a5c7cc7699d8357d79f2"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON
How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Loading timeline…




    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.