Description
In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: eir: Fix OOB read in eir_get_service_data()

eir_get_service_data() walks the advertising data for a Service Data
field with a matching UUID. On a mismatch it advances:

eir += dlen;
eir_len -= dlen;

eir_get_data() reports dlen as the field's data length, but the field
spans dlen + 2 bytes once its length and type bytes count, and more
when non-Service-Data fields were skipped to reach it. The pointer
lands correctly on the next field. eir_len does not, and the shortfall
compounds across fields until eir_get_data() reads the length and type
bytes of a "field" past the end of the buffer.

For an ISO broadcast sink that buffer is hcon->le_per_adv_data[], filled
from the periodic advertising reports of a remote broadcaster. A PA
payload packed with mismatching Service Data fields walks off the array
into the rest of struct hci_conn. A drifted field that matches the BAA
UUID puts those bytes in iso_pi(sk)->base, where user space reads them
back with getsockopt(BT_ISO_BASE).

Recompute eir_len from the end of the buffer each iteration.
Published: 2026-09-11
Score: 8.1 High
EPSS: < 1% Very Low
KEV: No
Impact: Information Disclosure
Action: Immediate Patch
AI Analysis

Impact

The flaw lies in how the Bluetooth eir_get_service routine mismanages the pointer and length counters for fields that do not match the expected UUID, causing the routine to read beyond the bounds of the advertising buffer. A remote attacker can craft a Bluetooth advertisement packet that contains mismatched Service Data fields, which triggers the out‑of‑bounds read. The kernel then copies memory from a location beyond the advertised buffer into a structure that is subsequently exposed to user space via the getsockopt(BT_ISO_BASE) interface. This results in a CWE‑125 out‑of‑bounds read that can leak kernel memory contents to an unprivileged user, compromising confidentiality.

Affected Systems

All Linux kernel builds that include the Bluetooth eir interface are affected, especially those accessing the le_per_adv_data[] field as described. The fix has been applied to the current kernel source mentioned in the advisory, but any kernel prior to that revision remains vulnerable. The vendor list indicates Linux, and the affected product is the Linux kernel as a whole.

Risk and Exploitability

The assigned CVSS score of 8.1 places this vulnerability in the high severity range. The EPSS score indicates a very low but non‑zero likelihood of exploitation, and it is not listed in the CISA KEV catalog. The likely attack vector is remote via Bluetooth, as based on the description it is inferred that an adversary with a Bluetooth transmitter can send the crafted packet to the host without requiring local privileges or user interaction. Because the flaw only leads to information disclosure and does not provide privilege escalation or denial of service, the overall exploitation likelihood is moderate for environments where rogue Bluetooth devices are a concern.

Generated by OpenCVE AI on September 15, 2026 at 21:38 UTC.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Upgrade the Linux kernel to a version that includes the eir_get_service_data patch for CVE-2026-89583
  • If the Linux system does not require Bluetooth functionality, disable the Bluetooth subsystem in the kernel configuration or unload the relevant modules to limit the reception of Bluetooth advertising packets from untrusted devices
  • Configure system firewall or ACL rules to limit Bluetooth traffic to trusted devices only

Generated by OpenCVE AI on September 15, 2026 at 21:38 UTC.

Tracking

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Advisories
Source ID Title
Debian DSA Debian DSA DSA-6528-1 linux security update
History

Mon, 14 Sep 2026 12:30:00 +0000


Sun, 13 Sep 2026 06:45:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 6.8, 'vector': 'CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H'}

cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H'}


Sat, 12 Sep 2026 00:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-125
References
Metrics threat_severity

None

cvssV3_1

{'score': 6.8, 'vector': 'CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H'}

threat_severity

Important


Fri, 11 Sep 2026 23:45:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: Bluetooth: eir: Fix OOB read in eir_get_service_data() eir_get_service_data() walks the advertising data for a Service Data field with a matching UUID. On a mismatch it advances: eir += dlen; eir_len -= dlen; eir_get_data() reports dlen as the field's data length, but the field spans dlen + 2 bytes once its length and type bytes count, and more when non-Service-Data fields were skipped to reach it. The pointer lands correctly on the next field. eir_len does not, and the shortfall compounds across fields until eir_get_data() reads the length and type bytes of a "field" past the end of the buffer. For an ISO broadcast sink that buffer is hcon->le_per_adv_data[], filled from the periodic advertising reports of a remote broadcaster. A PA payload packed with mismatching Service Data fields walks off the array into the rest of struct hci_conn. A drifted field that matches the BAA UUID puts those bytes in iso_pi(sk)->base, where user space reads them back with getsockopt(BT_ISO_BASE). Recompute eir_len from the end of the buffer each iteration.
Title Bluetooth: eir: Fix OOB read in eir_get_service_data()
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Subscriptions

Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-09-14T12:01:11.801Z

Reserved: 2026-09-11T19:38:34.728Z

Link: CVE-2026-89583

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-11T20:19:42.660

Modified: 2026-09-14T13:19:12.587

Link: CVE-2026-89583

cve-icon Redhat

Severity : Important

Publid Date: 2026-09-11T19:44:49Z

Links: CVE-2026-89583 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-09-15T21:45:17Z

Weaknesses