VulnerabilityPublished 18 Oct 2026

CVE-2026-98461: Linux kernel · Bluetooth: hci_sock: validate event length before filtering

Source GCVE Database

Authoritative record:CVE-2026-98461· Medium

Not known to be exploited · fixed in f894f6292d5122cd62d30600736b4a0ae79f7770 : update Linux kernel when convenient.

Data as of 26 Oct 2026, 12:55 UTC

Severity

Medium

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS: 0.2% chance of exploitation in 30 days – higher than 11% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in f894f6292d5122cd62d30600736b4a0ae79f7770, ebdd49cec380731844ed9df4092a29a014623df4, dca25c204f71be0556a15177dbe037237ac43e5e +5

Exploitation evidence

Disclosed: evidence found.
CVE published 18 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

ghsa-xggg-9q4f-8rr9

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < f894f6292d5122cd62d30600736b4a0ae79f7770	Fixed in f894f6292d5122cd62d30600736b4a0ae79f7770
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < ebdd49cec380731844ed9df4092a29a014623df4	Fixed in ebdd49cec380731844ed9df4092a29a014623df4
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < dca25c204f71be0556a15177dbe037237ac43e5e	Fixed in dca25c204f71be0556a15177dbe037237ac43e5e
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < b0a6cf99afd57a39598b1beca0e86ef5004980de	Fixed in b0a6cf99afd57a39598b1beca0e86ef5004980de
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 3976bbcd43b9b94c53ac9b0fd28888011588f4cc	Fixed in 3976bbcd43b9b94c53ac9b0fd28888011588f4cc
LinuxLinux	Affected ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 2501a3b7b7144d1d11939b355a48ed01f83d0c62	Fixed in 2501a3b7b7144d1d11939b355a48ed01f83d0c62

AI-suggested

A fix has been implemented in the Linux kernel to validate event lengths before filtering and to reject truncated command events. Users should update to the fixed Linux kernel version once available. Patch status is not explicitly stated in the provided data; therefore, check the vendor advisory for current remediation guidance.

Description

A vulnerability in the Linux kernel Bluetooth subsystem was resolved involving improper validation of event lengths before filtering. The function is_filtered_packet() reads event data without confirming the event buffer is sufficiently long, leading to potential out-of-bounds reads. This occurs when opcode filters are configured and malformed events are supplied by a controller or virtual host controller interface (vhci) device. The issue was fixed by rejecting truncated command events that are too short for inspection and correcting event code handling to prevent misclassification.

Impact

This vulnerability can cause out-of-bounds reads in kernel memory when processing malformed Bluetooth events, potentially leading to kernel crashes or information disclosure. However, no known exploits are reported in the wild. The impact is limited to systems with Bluetooth enabled and configured with opcode filters.

Summary

The Linux kernel Bluetooth vulnerability (CVE-2026-98461) involves the is_filtered_packet() function reading event codes from skb->data without verifying the buffer length, causing out-of-bounds reads when opcode filters are applied. Specifically, command opcodes at offsets 3 or 4 are accessed without length checks. The filtering occurs before event header validation, allowing malformed events from controllers or vhci devices to trigger the flaw. The fix includes rejecting truncated command events and correcting event code masking to avoid aliasing event codes, ensuring only valid events are processed.

References

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