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CVE-2026-98107

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: fix out-of-bounds write in l2cap_ecred_connect l2cap_chan_connect() tries to ensure there are no more than L2CAP_ECRED_CONN_SCID_MAX pending ECRED channels, so they fit in the same L2CAP_ECRED_CONN_REQ that l2cap_ecred_connect() constructs. However, the check only counts deferred channels. If 6 L2CAP sockets are connected at the same time in order DDDDND (D=deferred, N=non-deferred), the last can bump the total to max+1. It results to one __le16 written out of bounds of the scid array, and an invalid ECRED_CONN_REQ being sent. Fix by leaving room for the non-deferred pending ECRED channels in the counting in l2cap_chan_connect(), so the limit can't be exceeded. Move counting under same critical section where the channel is added. Although race conditions involving this appear unreachable, it's easier to see. Also add WARN_ON_ONCE check in l2cap_ecred_defer_connect() to make this less brittle.

Severity
Not scored
CVSS score
Not available
Vulnerability status
Undergoing Analysis
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-25 11:17:41.743000
Last modified
2026-10-21 13:21:22.877000
View original CVE JSON
{
  "id": "CVE-2026-98107",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-25T11:17:41.743",
  "lastModified": "2026-10-21T13:21:22.877",
  "vulnStatus": "Undergoing Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: fix out-of-bounds write in l2cap_ecred_connect\n\nl2cap_chan_connect() tries to ensure there are no more than\nL2CAP_ECRED_CONN_SCID_MAX pending ECRED channels, so they fit in the\nsame L2CAP_ECRED_CONN_REQ that l2cap_ecred_connect() constructs.\n\nHowever, the check only counts deferred channels.  If 6 L2CAP sockets\nare connected at the same time in order DDDDND (D=deferred,\nN=non-deferred), the last can bump the total to max+1.  It results to\none __le16 written out of bounds of the scid array, and an invalid\nECRED_CONN_REQ being sent.\n\nFix by leaving room for the non-deferred pending ECRED channels in the\ncounting in l2cap_chan_connect(), so the limit can't be exceeded.\n\nMove counting under same critical section where the channel is added.\nAlthough race conditions involving this appear unreachable, it's easier\nto see.\n\nAlso add WARN_ON_ONCE check in l2cap_ecred_defer_connect() to make this\nless brittle."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "net/bluetooth/l2cap_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "da49b602f7f75ccc91386e1274b3ef71676cd092",
              "lessThan": "fabc5e04f123225daf980d03f2c5a05e7f0f0a7f",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "da49b602f7f75ccc91386e1274b3ef71676cd092",
              "lessThan": "ce0927eb3ee2939fab5ce3f9334bfd2fafb38481",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "da49b602f7f75ccc91386e1274b3ef71676cd092",
              "lessThan": "6da5c0331fc3ef0c7b8df8269523fc3b2cce1e65",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "da49b602f7f75ccc91386e1274b3ef71676cd092",
              "lessThan": "df8c3af6132640da4788e96a02d653e642059803",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "da49b602f7f75ccc91386e1274b3ef71676cd092",
              "lessThan": "56c2b5831d39dc84aad2573dc3e197af1a872a05",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "net/bluetooth/l2cap_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5.7",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "5.7",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.6.160",
              "lessThanOrEqual": "6.6.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.12.111",
              "lessThanOrEqual": "6.12.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.53",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2.7",
              "lessThanOrEqual": "7.2.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/56c2b5831d39dc84aad2573dc3e197af1a872a05",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/6da5c0331fc3ef0c7b8df8269523fc3b2cce1e65",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/ce0927eb3ee2939fab5ce3f9334bfd2fafb38481",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/df8c3af6132640da4788e96a02d653e642059803",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/fabc5e04f123225daf980d03f2c5a05e7f0f0a7f",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}