VulnerabilityPublished 6 Oct 2026Updated 19 Oct 2026

CVE-2026-98304: Linux kernel · net: bcmgenet: restore the hardware filters on open

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in 906140955c8debde65afe12e594e04c49a61b0d9 : update Linux kernel when convenient.

Data as of 26 Oct 2026, 14:05 UTC

Severity

Medium

Rated Medium by Threat Radar's AI analysis · CVSS not yet scored by NVD

EPSS: 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 906140955c8debde65afe12e594e04c49a61b0d9, 56db7ec462d6a2b886e299ad835109c089606969, 23ca4ddc4fce2c233a49e9fd34d4b5b02bd7324e

Exploitation evidence

Disclosed: evidence found.
CVE published 6 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.

What to do

Upgrade Linux kernel to 906140955c8debde65afe12e594e04c49a61b0d9, 56db7ec462d6a2b886e299ad835109c089606969 or 23ca4ddc4fce2c233a49e9fd34d4b5b02bd7324e.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 3e370952287c55e5fd240cb8bb41ef8acff8829d, < 906140955c8debde65afe12e594e04c49a61b0d9	Fixed in 906140955c8debde65afe12e594e04c49a61b0d9
LinuxLinux	Affected ≥ 3e370952287c55e5fd240cb8bb41ef8acff8829d, < 56db7ec462d6a2b886e299ad835109c089606969	Fixed in 56db7ec462d6a2b886e299ad835109c089606969
LinuxLinux	Affected ≥ 3e370952287c55e5fd240cb8bb41ef8acff8829d, < 23ca4ddc4fce2c233a49e9fd34d4b5b02bd7324e	Fixed in 23ca4ddc4fce2c233a49e9fd34d4b5b02bd7324e
LinuxLinux	Affected =5.8	Fixed in–

AI-suggested

A fix is available and has been applied in the Linux kernel after version 5.8. Users should upgrade to a kernel version that includes the commits 906140955c8debde65afe12e594e04c49a61b0d9, 56db7ec462d6a2b886e299ad835109c089606969, or 23ca4ddc4fce2c233a49e9fd34d4b5b02bd7324e. No additional mitigation is required beyond applying the official patch.

Description

A vulnerability in the Linux kernel's bcmgenet network driver causes user-configured hardware filter rules to be silently lost when the network interface is brought down and back up. This occurs because the bcmgenet_hfb_init() function reinitializes the filter list on each interface open, dropping all previously configured rules. The issue has been fixed by initializing the filter lists once at probe time and restoring the rules on interface open.

Impact

User-configured hardware filter rules applied via ethtool are silently dropped whenever the network interface is brought down and then back up, potentially disrupting network traffic filtering policies. This could lead to unintended traffic being allowed or blocked, impacting network security and functionality. There is no indication of remote code execution or privilege escalation from this issue.

Summary

CVE-2026-98304 addresses a flaw in the Linux kernel's bcmgenet network driver where bcmgenet_hfb_init() calls INIT_LIST_HEAD() on priv->rxnfc_list during each interface open (bcmgenet_open()), which clears all user-configured hardware filter rules without notification. This results in loss of all ethtool-configured flow-type filters after the interface is cycled down and up. The fix involves initializing the filter lists only once during device probe and restoring the filter rules on interface open, similar to the existing bcmgenet_resume() behavior. The vulnerability affects Linux kernel version 5.8 and has been resolved in subsequent commits.

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 11:40 UTC

Technical details

References

Community reviews

Related threats