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Review reviewHigh

CVE-2026-53209

Linux Linux, linux kernel

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: reject oversized Broadcast Announcement prepend Existing advertising instances can already hold the maximum extended advertising payload. When hci_adv_bcast_annoucement() prepends the Broadcast Announcement service data to that payload, the combined data may no longer fit in the temporary buffer used to rebuild the advertising data. Reject that case before copying the existing payload and report the failure through the device log. This keeps the existing advertising data intact and avoids overrunning th...

CVSS
7.8
EPSS
0.13%
2.96% percentile
CISA KEV
Not listed
Published
2026.06.25
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability0.13%
Technical severityCVSS 7.8

Vulnerability overview

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_sync: reject oversized Broadcast Announcement prepend Existing advertising instances can already hold the maximum extended advertising payload. When hci_adv_bcast_annoucement() prepends the Broadcast Announcement service data to that payload, the combined data may no longer fit in the temporary buffer used to rebuild the advertising data. Reject that case before copying the existing payload and report the failure through the device log. This keeps the existing advertising data intact and avoids overrunning th...

Affected product and versions

Product
Linux Linux, linux kernel
Affected versions
63f365eb4d1668a04070151b555d55a07ede8d4b, c621211b308816889f0a3246de448bfcef8ab3ab, 907ef6e12fb558a0763e894311eb245a94c192dd, 5725bc608252050ed8a4d47d59225b7dd73474c8, 15da883c010cbc2a84aec1738b6ad6ee477846de, 6.1.142, 6.6.94, 6.12.34, 6.15.3, 6.16, >= 6.1.142 < 6.1.176, >= 6.6.94 < 6.6.143, >= 6.12.34 < 6.12.94, >= 6.15.3 < 6.16, >= 6.16.1 < 6.18.36, >= 6.19 < 7.0.13, 7.1
Fixed versions
6.1.176, 6.6.143, 6.12.94, 6.16, 6.18.36, 7.0.13

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that Linux Linux, linux kernel and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
CWE-787
CVE-2026-53209 — Linux Linux, linux kernel | SECUFOCUS NOW