VulnerabilityPublished 19 Jul 2026

CVE-2026-63998: Linux kernel · ethtool: module: call ethnl_ops_complete() on module flash errors

Source GCVE Database

Authoritative record:CVE-2026-63998

Not known to be exploited · CVSS 5.5 Medium · fixed in e96ef1a40dda5b637b1911cd950b11e9848de939 : update Linux kernel when convenient.

Data as of 26 Oct 2026, 14:05 UTC

CVSS 3.1 base score

5.5Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.1% chance of exploitation in 30 days – higher than 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in e96ef1a40dda5b637b1911cd950b11e9848de939, d9defbf8b62bde89e206d74c2a2b445b9ed66108, 84371fb58423f997939aacdcbc02d128d76a54e5 +1

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack Vector: Local
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 19 Jul 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-j457-3527-85c4

What to do

Upgrade Linux kernel to e96ef1a40dda5b637b1911cd950b11e9848de939, d9defbf8b62bde89e206d74c2a2b445b9ed66108, 84371fb58423f997939aacdcbc02d128d76a54e5 or 170d82a57f4be1ce83de823a93bafd218a0d5fb1.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 32b4c8b53ee7799e34a2b1634d32d3ce1e36c44e, < e96ef1a40dda5b637b1911cd950b11e9848de939	Fixed in e96ef1a40dda5b637b1911cd950b11e9848de939
LinuxLinux	Affected ≥ 32b4c8b53ee7799e34a2b1634d32d3ce1e36c44e, < d9defbf8b62bde89e206d74c2a2b445b9ed66108	Fixed in d9defbf8b62bde89e206d74c2a2b445b9ed66108
LinuxLinux	Affected ≥ 32b4c8b53ee7799e34a2b1634d32d3ce1e36c44e, < 84371fb58423f997939aacdcbc02d128d76a54e5	Fixed in 84371fb58423f997939aacdcbc02d128d76a54e5
LinuxLinux	Affected ≥ 32b4c8b53ee7799e34a2b1634d32d3ce1e36c44e, < 170d82a57f4be1ce83de823a93bafd218a0d5fb1	Fixed in 170d82a57f4be1ce83de823a93bafd218a0d5fb1
LinuxLinux	Affected =6.11	Fixed in–

AI-suggested

A fix has been implemented in the Linux kernel to address this issue by ensuring ethnl_ops_complete() is called on module flash errors. Users should apply the official kernel updates that include this fix. Patch status is not explicitly confirmed in the provided data; therefore, check the vendor or Linux kernel advisories for the current remediation guidance.

Description

A vulnerability in the Linux kernel's ethtool module was resolved involving improper handling of module flash errors. Specifically, when the validate() function fails, the ethnl_ops_complete() call is skipped despite an earlier call to ethnl_ops_begin(), potentially leading to inconsistent module state handling.

Impact

The impact details are not explicitly provided. However, the issue relates to incomplete operation completion calls during module flash errors, which could potentially lead to inconsistent kernel module states or resource handling. No known exploits in the wild have been reported.

Summary

The Linux kernel ethtool module contained a flaw where, upon failure of the validate() function during module flash operations, the ethnl_ops_complete() function was not called even though ethnl_ops_begin() had already been invoked. This discrepancy could cause improper completion handling of module flash errors. The vulnerability has been resolved by ensuring ethnl_ops_complete() is called appropriately on module flash errors.

References

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