Vulnerabilities in pkg:golang/github.com/siderolabs/talos

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-m38g-vww2-mvgx",
  "modified" : "2026-06-08T23:43:27Z",
  "published" : "2026-05-07T02:38:02Z",
  "aliases" : [ ],
  "summary" : "Talos Linux has a local privilege escalation from untrusted workloads",
  "details" : "### Summary\n\nA vulnerability in the Linux kernel's algif_aead subsystem (CVE-2026-31431, \"copy.fail\") allows an unprivileged container workload to corrupt arbitrary file page-cache pages via the AF_ALG crypto interface and splice(). On Talos Linux, this vulnerability can be chained into a complete node compromise: an attacker who can schedule a pod on a worker node can, without any elevated Kubernetes permissions, achieve arbitrary code execution as root on the host (by poisoning a binary inside a privileged pod, or poisoning a binary which runs with elevated privileges like a CNI binary), access host filesystem, including node secrets. \n\nThe exploit does not require kernel debugging, race conditions, or any prior privileges beyond the ability to create a pod.\n\n### Impact\n\nAn attacker with the ability to deploy a Kubernetes pod on an affected node can:\n\n1. Corrupt the page-cache of /usr/sbin/nft in the containerd snapshot layer shared between the attacker's pod and the kube-proxy DaemonSet. Because containerd reuses XFS page-cache pages across overlayfs mounts sharing the same lower layer, the corruption is immediately visible to all containers using that image layer — including privileged system DaemonSets.\n2. Execute arbitrary code inside kube-proxy — a privileged DaemonSet running on every node with all Linux capabilities (privileged: true) and host network access — the next time kube-proxy invokes nft as part of its nftables reconciliation loop (typically within seconds).\n3. At this point, an attacker achieved code execution inside a privileged pod, which allows to escape to the host.\n4. Same attack can be planted by infiltrating other binaries running as privileged, for example a CNI plugin.\n\n### Patches\n\nUpgrade to Talos v1.13.0 or Talos v1.12.7 which ships Linux kernel 6.18.25. The kernel fix for CVE-2026-31431 (algif_aead in-place optimization revert) was committed upstream in  Linux 6.18.22 and is included in all Talos releases from v1.13.0 and Talos 1.12.7 onwards.\n\n### Workarounds\n\nThere are multiple workarounds available based on the situation, but we really recommend to upgrade.\n\n#### Option 1 - Change kernel arguments\n\nAdd a kernel argument with `initcall_blacklist=algif_aead_init` by upgrading Talos to the same version.\n\n> Note: this either requires setting `machine.kernel.extraKernelArgs` if using BIOS based boot or upgrading with a new image from factory/imager generated image by setting the extra kernel args. See [Boot Assets](https://docs.siderolabs.com/talos/v1.13/platform-specific-installations/boot-assets)\n\n#### Option 2 - Deploy all workload pods with a seccomp profile denying  creating `AF_ALG` socket creation\n\n`patch.yaml`\n\n```yaml\nmachine:\n  seccompProfiles:\n    - name: copy-fail-block.json\n      value:\n        defaultAction: SCMP_ACT_ALLOW\n        syscalls:\n          - names:\n              - socket\n            action: SCMP_ACT_ERRNO\n            args:\n              - index: 0\n                value: 38\n                op: SCMP_CMP_EQ\n```\n\nApply this patch to all machines in the cluster and set this for all the pod spec:\n\n```yaml\n...\nspec:\n      securityContext:\n        seccompProfile:\n          type: Localhost\n          localhostProfile: profiles/copy-fail-block.json\n```\n\n#### Option 3 - Block the syscall in runtime with a eBPF program\n\nSee [copy-fail-blocker](https://github.com/cozystack/copy-fail-blocker), this can be applied to a running system without a reboot, but it has to run before any other workloads are scheduled after a reboot. \n\n### References\n\n* https://copy.fail/\n* https://xint.io/blog/copy-fail-linux-distributions\n* https://github.com/theori-io/copy-fail-CVE-2026-31431\n* https://github.com/Percivalll/Copy-Fail-CVE-2026-31431-Kubernetes-PoC",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/siderolabs/talos"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.12.7"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/siderolabs/talos/security/advisories/GHSA-m38g-vww2-mvgx"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-31431"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/Percivalll/Copy-Fail-CVE-2026-31431-Kubernetes-PoC"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/siderolabs/talos"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/theori-io/copy-fail-CVE-2026-31431"
  }, {
    "type" : "WEB",
    "url" : "https://xint.io/blog/copy-fail-linux-distributions"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-669" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-07T02:38:02Z",
    "nvd_published_at" : null
  }
}