{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "a8599bd821d084d04a3290fffae1071624ec00ea"
            },
            {
              "fixed": "9081c71796724ffe96cba253f68fbe42363c5295"
            },
            {
              "fixed": "03b417afce19ee6b6e61f1bbbbebac924c9f36d1"
            },
            {
              "fixed": "a4228b93706fb74a484e6ffb271c1cc2af3a2ddb"
            },
            {
              "fixed": "71893c342a26bcff92eaab0b2b75d64aed19308a"
            },
            {
              "fixed": "4dbc71bcaf9a30abf3920a4e2cc4ed33bba78c02"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.6.34"
            },
            {
              "fixed": "6.6.148"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.101"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.42"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68160.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nceph: fix pre-auth out-of-bounds read on snaptrace in ceph_handle_caps()\n\nceph_handle_caps() reads snap_trace_len from the wire-format\nceph_mds_caps header and uses it unconditionally to build a fake\nend pointer (snaptrace + snaptrace_len) that is later handed to\nceph_update_snap_trace() in the CEPH_CAP_OP_IMPORT case:\n\n    snaptrace     = h + 1;\n    snaptrace_len = le32_to_cpu(h-\u003esnap_trace_len);\n    p             = snaptrace + snaptrace_len;\n    ...\n    case CEPH_CAP_OP_IMPORT:\n        if (snaptrace_len) {\n            ...\n            if (ceph_update_snap_trace(mdsc, snaptrace,\n                                       snaptrace + snaptrace_len,\n                                       false, \u0026realm)) { ... }\n\nceph_update_snap_trace() then decodes a struct ceph_mds_snap_realm\nfrom snaptrace using ceph_decode_need(\u0026p, e, sizeof(*ri), bad)\nwith the attacker-supplied fake end e == snaptrace + snaptrace_len.\nWith snaptrace_len == 0xFFFFFFFF the bound check is trivially\nsatisfied, ri = p reads sizeof(struct ceph_mds_snap_realm) past\nthe legitimate msg-\u003efront buffer, and ri-\u003enum_snaps /\nri-\u003enum_prior_parent_snaps then drive further out-of-bounds\nreads of the encoded snap arrays.\n\nThe eleven msg_version \u003e= 2 .. msg_version \u003e= 12 decoder blocks\nabove the op switch each catch this OOB through their\nceph_decode_*_safe() / ceph_decode_need() helpers, but they sit\nbehind a hdr.version-gated if, so a malicious or compromised\nMDS that sets msg-\u003ehdr.version = 1 reaches the IMPORT path with\nno version-gated decoder having validated snap_trace_len. The\nshape has been present since ceph_handle_caps() was introduced.\n\nValidate snap_trace_len against the message front buffer before\nconsuming it, using the canonical ceph_decode_need() / ceph_has_room()\nhelper.  The helper bounds the length with subtraction (n \u003c= end - p,\nguarded by end \u003e= p) rather than pointer addition, so it is wrap-safe\nfor the attacker-controlled u32 length on 32-bit builds where\np + snap_trace_len could overflow the address space.  This matches the\nrest of the ceph decode path (e.g. the pool_ns_len check a few lines\nbelow), and the existing goto bad cleanup already covers this exit\npath.",
  "id": "CVE-2026-68160",
  "modified": "2026-08-18T03:31:14.052229297Z",
  "published": "2026-08-10T11:59:26.741Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/03b417afce19ee6b6e61f1bbbbebac924c9f36d1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4dbc71bcaf9a30abf3920a4e2cc4ed33bba78c02"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/71893c342a26bcff92eaab0b2b75d64aed19308a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9081c71796724ffe96cba253f68fbe42363c5295"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a4228b93706fb74a484e6ffb271c1cc2af3a2ddb"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68160.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-68160"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "ceph: fix pre-auth out-of-bounds read on snaptrace in ceph_handle_caps()"
}