CVE-2026-68420

{
  "id": "CVE-2026-68420",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 7.1,
          "attackVector": "LOCAL",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.2,
        "exploitabilityScore": 1.8
      }
    ]
  },
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "d1716d5a44c37e5743bf6ea4e5cdbdab37727f27",
              "lessThan": "d7fc6f351c478586980a521d63b0214d9c055e78",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "d1716d5a44c37e5743bf6ea4e5cdbdab37727f27",
              "lessThan": "9333f4b6f44858fc98eb12bf26b8d2959eb975d5",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "d1716d5a44c37e5743bf6ea4e5cdbdab37727f27",
              "lessThan": "ea528f18231ec0f33317be57f8866913b19aba6e",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "net/xfrm/xfrm_user.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.14"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "6.14",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "6.18.42",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "status": "unaffected",
              "version": "7.1.6",
              "versionType": "semver",
              "lessThanOrEqual": "7.1.*"
            },
            {
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "net/xfrm/xfrm_user.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2026-08-10T13:20:35.840",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/9333f4b6f44858fc98eb12bf26b8d2959eb975d5",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/d7fc6f351c478586980a521d63b0214d9c055e78",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ea528f18231ec0f33317be57f8866913b19aba6e",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Received",
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: reject optional IPTFS templates in outbound policies\n\nsyzbot reported a stack-out-of-bounds read in xfrm_state_find()\nwhich flows from xfrm_tmpl_resolve_one().\n\nCommit 3d776e31c841 (\"xfrm: Reject optional tunnel/BEET mode\ntemplates in outbound policies\") disallowed optional tunnel and\nBEET in outbound policies to prevent this. Later when IPTFS\nadded, it was not covered by that fix and can still trigger\nthe out-of-bounds read;\n\nExtend the check to disallow optional IPTFS in outbound policies\nas well. IPTFS should be identical to tunnel mode.\nIN and FWD policies are not affected: xfrm_tmpl_resolve_one()\nis only reachable via the outbound path.\n\nReproducer, before:\n\nip link add dummy0 type dummy\nip link set dummy0 up\nip addr add 10.1.1.1/24 dev dummy0\nip xfrm policy add src 10.1.1.1/32 dst 10.1.1.2/32 dir out tmpl\n  src fc00::dead:1 dst fc00::dead:2 proto esp reqid 1 mode iptfs\n  level use tmpl src fc00::dead:1 dst fc00::dead:2 proto esp reqid\n  2 mode transport\nping -W 1 -c 1 10.1.1.2\nPING 10.1.1.2 (10.1.1.2) 56(84) bytes of data.\n\n[   64.168420] ==================================================================\n[   64.169977] BUG: KASAN: stack-out-of-bounds in __xfrm6_addr_hash+0x11e/0x170\n[   64.169977] Read of size 4 at addr ffff88800e1ffd20 by task ping/2844\n\n[   64.169977] CPU: 2 UID: 0 PID: 2844 Comm: ping Not tainted 7.1.0-rc7-00180-geb23b588430a #98 PREEMPT(full)\n[   64.169977] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n[   64.169977] Call Trace:\n[   64.169977]  <TASK>\n[   64.169977]  dump_stack_lvl+0x47/0x70\n[   64.169977]  ? __xfrm6_addr_hash+0x11e/0x170\n[   64.169977]  print_report+0x152/0x4b0\n[   64.169977]  ? ksys_mmap_pgoff+0x6d/0xa0\n[   64.169977]  ? entry_SYSCALL_64_after_hwframe+0x76/0x7e\n[   64.169977]  ? rcu_read_unlock_sched+0xa/0x20\n[   64.169977]  ? __virt_addr_valid+0x21b/0x230\n[   64.169977]  ? __xfrm6_addr_hash+0x11e/0x170\n[   64.169977]  kasan_report+0xa8/0xd0\n[   64.169977]  ? __xfrm6_addr_hash+0x11e/0x170\n[   64.169977]  __xfrm6_addr_hash+0x11e/0x170\n[   64.169977]  __xfrm_dst_hash+0x24/0xc0\n[   64.169977]  xfrm_state_find+0xa2d/0x2f90\n[   64.169977]  ? __pfx_xfrm_state_find+0x10/0x10\n[   64.169977]  ? __pfx_ftrace_graph_ret_addr+0x10/0x10\n[   64.169977]  ? __pfx_ftrace_graph_ret_addr+0x10/0x10\n[   64.169977]  xfrm_tmpl_resolve_one+0x210/0x570\n[   64.169977]  ? __pfx_xfrm_tmpl_resolve_one+0x10/0x10\n[   64.169977]  ? __pfx_stack_trace_consume_entry+0x10/0x10\n[   64.169977]  ? kernel_text_address+0x5b/0x80\n[   64.169977]  ? __kernel_text_address+0xe/0x30\n[   64.169977]  ? unwind_get_return_address+0x5e/0x90\n[   64.169977]  ? arch_stack_walk+0x8c/0xe0\n[   64.169977]  xfrm_tmpl_resolve+0x130/0x200\n[   64.169977]  ? __pfx_xfrm_tmpl_resolve+0x10/0x10\n[   64.169977]  ? __pfx_xfrm_policy_inexact_lookup_rcu+0x10/0x10\n[   64.169977]  ? __refcount_add_not_zero.constprop.0+0xb2/0x110\n[   64.169977]  ? __pfx___refcount_add_not_zero.constprop.0+0x10/0x10\n[   64.169977]  xfrm_resolve_and_create_bundle+0xd5/0x310\n[   64.169977]  ? __pfx_xfrm_resolve_and_create_bundle+0x10/0x10\n[   64.169977]  ? __pfx_xfrm_policy_lookup_bytype+0x10/0x10\n[   64.169977]  ? __pfx_xfrm_policy_lookup_bytype+0x10/0x10\n[   64.169977]  xfrm_lookup_with_ifid+0x3d8/0xb80\n[   64.169977]  ? __pfx_xfrm_lookup_with_ifid+0x10/0x10\n[   64.169977]  ? ip_route_output_key_hash+0xc6/0x110\n[   64.169977]  ? kasan_save_track+0x10/0x30\n[   64.169977]  xfrm_lookup_route+0x18/0xe0\n[   64.169977]  ip4_datagram_release_cb+0x4c9/0x530\n[   64.169977]  ? __pfx_ip4_datagram_release_cb+0x10/0x10\n[   64.169977]  ? do_raw_spin_lock+0x71/0xc0\n[   64.169977]  ? __pfx_do_raw_spin_lock+0x10/0x10\n[   64.169977]  release_sock+0xb0/0x170\n[   64.169977]  udp_connect+0x43/0x50\n[   64.169977]  __sys_connect+0xa6/0x100\n[   64.169977]  ? alloc_fd+0x2e9/0x300\n[   64.169977]  ? __pfx___sys_connect+0x10/0x10\n[   64.169977]  ? preempt_latency\n---truncated---"
    }
  ],
  "lastModified": "2026-08-17T06:17:51.013",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}