Vulnerability-Lookup

EUVD-2026-320964

European Vulnerability Database identifier assigned by ENISA

Reserved

2026-10-02 07:43

Assigner

ENISA

Alias of

a CVE record, shown under related vulnerabilities. This identifier carries no description, severity or references of its own: they belong to that CVE.

JSON

To clipboard

{
  "assigner": "ENISA",
  "date_reserved": "2026-10-02T07:43:17.197263+00:00",
  "id": "EUVD-2026-320964"
}

CVE-2026-31498 (GCVE-0-2026-31498)

Vulnerability from cvelistv5 – Published: 2026-04-22 13:54 – Updated: 2026-05-23 16:05

Title

Bluetooth: L2CAP: Fix ERTM re-init and zero pdu_len infinite loop

Summary

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix ERTM re-init and zero pdu_len infinite loop l2cap_config_req() processes CONFIG_REQ for channels in BT_CONNECTED state to support L2CAP reconfiguration (e.g. MTU changes). However, since both CONF_INPUT_DONE and CONF_OUTPUT_DONE are already set from the initial configuration, the reconfiguration path falls through to l2cap_ertm_init(), which re-initializes tx_q, srej_q, srej_list, and retrans_list without freeing the previous allocations and sets chan->sdu to NULL without freeing the existing skb. This leaks all previously allocated ERTM resources. Additionally, l2cap_parse_conf_req() does not validate the minimum value of remote_mps derived from the RFC max_pdu_size option. A zero value propagates to l2cap_segment_sdu() where pdu_len becomes zero, causing the while loop to never terminate since len is never decremented, exhausting all available memory. Fix the double-init by skipping l2cap_ertm_init() and l2cap_chan_ready() when the channel is already in BT_CONNECTED state, while still allowing the reconfiguration parameters to be updated through l2cap_parse_conf_req(). Also add a pdu_len zero check in l2cap_segment_sdu() as a safeguard.

Severity

No CVSS data available.

Assigner

Linux mitre root Scorecard

References

8 references

URL	Tags
https://git.kernel.org/stable/c/9760b83cfd24b38ca…
https://git.kernel.org/stable/c/de37e2655b7abc3f5…
https://git.kernel.org/stable/c/e7aab23b7df89a3d7…
https://git.kernel.org/stable/c/52667c859fe33f70c…
https://git.kernel.org/stable/c/9a21a631ee034b157…
https://git.kernel.org/stable/c/900e4db5385ec2cac…
https://git.kernel.org/stable/c/042e2cd4bb11e5313…
https://git.kernel.org/stable/c/25f420a0d4cfd61d3…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 96298f640104e4cd9a913a6e50b0b981829b94ff , < 9760b83cfd24b38caee663f429011a0dd6064fa9 (git) Affected: 96298f640104e4cd9a913a6e50b0b981829b94ff , < de37e2655b7abc3f59254c6b72256840f39fc6d5 (git) Affected: 96298f640104e4cd9a913a6e50b0b981829b94ff , < e7aab23b7df89a3d754a5f0a7d2237548b328bd0 (git) Affected: 96298f640104e4cd9a913a6e50b0b981829b94ff , < 52667c859fe33f70c2e711cb81bbd505d5eb8e75 (git) Affected: 96298f640104e4cd9a913a6e50b0b981829b94ff , < 9a21a631ee034b1573dce14b572a24943dbfd7ae (git) Affected: 96298f640104e4cd9a913a6e50b0b981829b94ff , < 900e4db5385ec2cacd372345a80ab9c8e105b3a3 (git) Affected: 96298f640104e4cd9a913a6e50b0b981829b94ff , < 042e2cd4bb11e5313b19b87593616524949e4c52 (git) Affected: 96298f640104e4cd9a913a6e50b0b981829b94ff , < 25f420a0d4cfd61d3d23ec4b9c56d9f443d91377 (git) Affected: 4ad03ff6f680681c5f78254e37c4c856fa953629 (git) Affected: b7d0ca715c1008acd2fc018f02a56fed88f78b75 (git) Affected: 799263eb37a4f7f6d39334046929c3bc92452a7f (git) Affected: 8828622fb9b4201eeb0870587052e3d834cfaf61 (git) Affected: b432ea85ab8472763870dd0f2c186130dd36d68c (git) Affected: 4.4.238 , < 4.5 (semver) Affected: 4.9.238 , < 4.10 (semver) Affected: 4.14.200 , < 4.15 (semver) Affected: 4.19.149 , < 4.20 (semver) Affected: 5.4.69 , < 5.5 (semver)
Linux	Linux	Affected: 5.7 Unaffected: 0 , < 5.7 (semver) Unaffected: 5.10.253 , ≤ 5.10.* (semver) Unaffected: 5.15.203 , ≤ 5.15.* (semver) Unaffected: 6.1.168 , ≤ 6.1.* (semver) Unaffected: 6.6.131 , ≤ 6.6.* (semver) Unaffected: 6.12.80 , ≤ 6.12.* (semver) Unaffected: 6.18.21 , ≤ 6.18.* (semver) Unaffected: 6.19.11 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/bluetooth/l2cap_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "9760b83cfd24b38caee663f429011a0dd6064fa9",
              "status": "affected",
              "version": "96298f640104e4cd9a913a6e50b0b981829b94ff",
              "versionType": "git"
            },
            {
              "lessThan": "de37e2655b7abc3f59254c6b72256840f39fc6d5",
              "status": "affected",
              "version": "96298f640104e4cd9a913a6e50b0b981829b94ff",
              "versionType": "git"
            },
            {
              "lessThan": "e7aab23b7df89a3d754a5f0a7d2237548b328bd0",
              "status": "affected",
              "version": "96298f640104e4cd9a913a6e50b0b981829b94ff",
              "versionType": "git"
            },
            {
              "lessThan": "52667c859fe33f70c2e711cb81bbd505d5eb8e75",
              "status": "affected",
              "version": "96298f640104e4cd9a913a6e50b0b981829b94ff",
              "versionType": "git"
            },
            {
              "lessThan": "9a21a631ee034b1573dce14b572a24943dbfd7ae",
              "status": "affected",
              "version": "96298f640104e4cd9a913a6e50b0b981829b94ff",
              "versionType": "git"
            },
            {
              "lessThan": "900e4db5385ec2cacd372345a80ab9c8e105b3a3",
              "status": "affected",
              "version": "96298f640104e4cd9a913a6e50b0b981829b94ff",
              "versionType": "git"
            },
            {
              "lessThan": "042e2cd4bb11e5313b19b87593616524949e4c52",
              "status": "affected",
              "version": "96298f640104e4cd9a913a6e50b0b981829b94ff",
              "versionType": "git"
            },
            {
              "lessThan": "25f420a0d4cfd61d3d23ec4b9c56d9f443d91377",
              "status": "affected",
              "version": "96298f640104e4cd9a913a6e50b0b981829b94ff",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "4ad03ff6f680681c5f78254e37c4c856fa953629",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "b7d0ca715c1008acd2fc018f02a56fed88f78b75",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "799263eb37a4f7f6d39334046929c3bc92452a7f",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "8828622fb9b4201eeb0870587052e3d834cfaf61",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "b432ea85ab8472763870dd0f2c186130dd36d68c",
              "versionType": "git"
            },
            {
              "lessThan": "4.5",
              "status": "affected",
              "version": "4.4.238",
              "versionType": "semver"
            },
            {
              "lessThan": "4.10",
              "status": "affected",
              "version": "4.9.238",
              "versionType": "semver"
            },
            {
              "lessThan": "4.15",
              "status": "affected",
              "version": "4.14.200",
              "versionType": "semver"
            },
            {
              "lessThan": "4.20",
              "status": "affected",
              "version": "4.19.149",
              "versionType": "semver"
            },
            {
              "lessThan": "5.5",
              "status": "affected",
              "version": "5.4.69",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/bluetooth/l2cap_core.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.7"
            },
            {
              "lessThan": "5.7",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.10.*",
              "status": "unaffected",
              "version": "5.10.253",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "5.15.*",
              "status": "unaffected",
              "version": "5.15.203",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.168",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.131",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.80",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.21",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.11",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.10.253",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "5.15.203",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.1.168",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.131",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.80",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.21",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.11",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "5.7",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "4.4.238",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "4.9.238",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "4.14.200",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "4.19.149",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionStartIncluding": "5.4.69",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "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."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-23T16:05:11.217Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/9760b83cfd24b38caee663f429011a0dd6064fa9"
        },
        {
          "url": "https://git.kernel.org/stable/c/de37e2655b7abc3f59254c6b72256840f39fc6d5"
        },
        {
          "url": "https://git.kernel.org/stable/c/e7aab23b7df89a3d754a5f0a7d2237548b328bd0"
        },
        {
          "url": "https://git.kernel.org/stable/c/52667c859fe33f70c2e711cb81bbd505d5eb8e75"
        },
        {
          "url": "https://git.kernel.org/stable/c/9a21a631ee034b1573dce14b572a24943dbfd7ae"
        },
        {
          "url": "https://git.kernel.org/stable/c/900e4db5385ec2cacd372345a80ab9c8e105b3a3"
        },
        {
          "url": "https://git.kernel.org/stable/c/042e2cd4bb11e5313b19b87593616524949e4c52"
        },
        {
          "url": "https://git.kernel.org/stable/c/25f420a0d4cfd61d3d23ec4b9c56d9f443d91377"
        }
      ],
      "title": "Bluetooth: L2CAP: Fix ERTM re-init and zero pdu_len infinite loop",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-31498",
    "datePublished": "2026-04-22T13:54:19.714Z",
    "dateReserved": "2026-03-09T15:48:24.103Z",
    "dateUpdated": "2026-05-23T16:05:11.217Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

EUVD-2026-320964

CVE-2026-31498 (GCVE-0-2026-31498)

Tags

Sightings

Nomenclature

Related by attack behaviour