{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "96298f640104e4cd9a913a6e50b0b981829b94ff"
            },
            {
              "fixed": "9760b83cfd24b38caee663f429011a0dd6064fa9"
            },
            {
              "fixed": "de37e2655b7abc3f59254c6b72256840f39fc6d5"
            },
            {
              "fixed": "e7aab23b7df89a3d754a5f0a7d2237548b328bd0"
            },
            {
              "fixed": "52667c859fe33f70c2e711cb81bbd505d5eb8e75"
            },
            {
              "fixed": "9a21a631ee034b1573dce14b572a24943dbfd7ae"
            },
            {
              "fixed": "900e4db5385ec2cacd372345a80ab9c8e105b3a3"
            },
            {
              "fixed": "042e2cd4bb11e5313b19b87593616524949e4c52"
            },
            {
              "fixed": "25f420a0d4cfd61d3d23ec4b9c56d9f443d91377"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "4ad03ff6f680681c5f78254e37c4c856fa953629"
            },
            {
              "last_affected": "b7d0ca715c1008acd2fc018f02a56fed88f78b75"
            },
            {
              "last_affected": "799263eb37a4f7f6d39334046929c3bc92452a7f"
            },
            {
              "last_affected": "8828622fb9b4201eeb0870587052e3d834cfaf61"
            },
            {
              "last_affected": "b432ea85ab8472763870dd0f2c186130dd36d68c"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "4.4.238"
            },
            {
              "fixed": "4.5"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "4.9.238"
            },
            {
              "fixed": "4.10"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "4.14.200"
            },
            {
              "fixed": "4.15"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "4.19.149"
            },
            {
              "fixed": "4.20"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "5.4.69"
            },
            {
              "fixed": "5.5"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.7.0"
            },
            {
              "fixed": "5.10.253"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.203"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.168"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.131"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.80"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.21"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "6.19.11"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31498.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: Fix ERTM re-init and zero pdu_len infinite loop\n\nl2cap_config_req() processes CONFIG_REQ for channels in BT_CONNECTED\nstate to support L2CAP reconfiguration (e.g. MTU changes). However,\nsince both CONF_INPUT_DONE and CONF_OUTPUT_DONE are already set from\nthe initial configuration, the reconfiguration path falls through to\nl2cap_ertm_init(), which re-initializes tx_q, srej_q, srej_list, and\nretrans_list without freeing the previous allocations and sets\nchan-\u003esdu to NULL without freeing the existing skb. This leaks all\npreviously allocated ERTM resources.\n\nAdditionally, l2cap_parse_conf_req() does not validate the minimum\nvalue of remote_mps derived from the RFC max_pdu_size option. A zero\nvalue propagates to l2cap_segment_sdu() where pdu_len becomes zero,\ncausing the while loop to never terminate since len is never\ndecremented, exhausting all available memory.\n\nFix the double-init by skipping l2cap_ertm_init() and\nl2cap_chan_ready() when the channel is already in BT_CONNECTED state,\nwhile still allowing the reconfiguration parameters to be updated\nthrough l2cap_parse_conf_req(). Also add a pdu_len zero check in\nl2cap_segment_sdu() as a safeguard.",
  "id": "CVE-2026-31498",
  "modified": "2026-07-08T05:38:42.538488727Z",
  "published": "2026-04-22T13:54:19.714Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/042e2cd4bb11e5313b19b87593616524949e4c52"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/25f420a0d4cfd61d3d23ec4b9c56d9f443d91377"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/52667c859fe33f70c2e711cb81bbd505d5eb8e75"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/900e4db5385ec2cacd372345a80ab9c8e105b3a3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9760b83cfd24b38caee663f429011a0dd6064fa9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9a21a631ee034b1573dce14b572a24943dbfd7ae"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/de37e2655b7abc3f59254c6b72256840f39fc6d5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e7aab23b7df89a3d754a5f0a7d2237548b328bd0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31498.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31498"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "summary": "Bluetooth: L2CAP: Fix ERTM re-init and zero pdu_len infinite loop"
}