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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
HIGH
CVSS score
7.8 (v3.1)
Vulnerability status
Analyzed
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-09-25 11:17:41.743000
Last modified
2026-11-12 18:28:34.740000
View original CVE JSON 
{
  "id": "CVE-2026-98107",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-09-25T11:17:41.743",
  "lastModified": "2026-11-12T18:28:34.740",
  "vulnStatus": "Analyzed",
  "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": [
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      "affectedData": [
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            },
            {
              "version": "7.3",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
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      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Primary",
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          "baseSeverity": "HIGH",
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          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
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  "weaknesses": [
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      "description": [
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}