VulnerabilityPublished 18 Oct 2026

CVE-2026-98526: Linux kernel · llc: reserve device headroom for allocated frames

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in e06f8b6e27cc616d3c587e9784c4a033eb310a16 : update Linux kernel when convenient.

Data as of 26 Oct 2026, 13:47 UTC

Severity

Medium

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 12% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in e06f8b6e27cc616d3c587e9784c4a033eb310a16, 1937222c2511ac91377d39f28106c34734f5f8c6, 018020f5a48cc86fdd6dc2d380f6c70443ae7639 +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.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ bf9ae5386bca8836c16e69ab8fdbe46767d7452a, < e06f8b6e27cc616d3c587e9784c4a033eb310a16	Fixed in e06f8b6e27cc616d3c587e9784c4a033eb310a16
LinuxLinux	Affected ≥ bf9ae5386bca8836c16e69ab8fdbe46767d7452a, < 1937222c2511ac91377d39f28106c34734f5f8c6	Fixed in 1937222c2511ac91377d39f28106c34734f5f8c6
LinuxLinux	Affected ≥ bf9ae5386bca8836c16e69ab8fdbe46767d7452a, < 018020f5a48cc86fdd6dc2d380f6c70443ae7639	Fixed in 018020f5a48cc86fdd6dc2d380f6c70443ae7639
LinuxLinux	Affected ≥ bf9ae5386bca8836c16e69ab8fdbe46767d7452a, < 3361c93e417384ebf28003e0fb6d5304653d3b05	Fixed in 3361c93e417384ebf28003e0fb6d5304653d3b05
LinuxLinux	Affected ≥ bf9ae5386bca8836c16e69ab8fdbe46767d7452a, < 72b5b9a28b996e09b8b5b944370c79851bb68f52	Fixed in 72b5b9a28b996e09b8b5b944370c79851bb68f52
LinuxLinux	Affected ≥ bf9ae5386bca8836c16e69ab8fdbe46767d7452a, < 16ceac2daa89dd16917bc488ab05b9dd6961a603	Fixed in 16ceac2daa89dd16917bc488ab05b9dd6961a603

AI-suggested

A fix is available and has been applied in the Linux kernel source. Users should update to the fixed versions containing the patch identified by the provided commit hashes. No additional mitigation steps are required beyond applying the official fix.

Description

A vulnerability in the Linux kernel's LLC (Logical Link Control) layer was fixed by properly reserving device headroom for allocated frames. The issue involved insufficient reservation of link-layer headroom for stacked Ethernet devices such as VLAN devices, which could cause skb headroom underflow during LLC responses. The fix uses LL_RESERVED_SPACE() to correctly account for the required headroom while preserving existing device-type checks.

Impact

The vulnerability could lead to skb headroom underflow in the kernel's network stack when handling LLC responses on VLAN or other stacked Ethernet devices. This may cause memory corruption or instability in network packet processing. However, no known exploits in the wild have been reported.

Summary

CVE-2026-98526 addresses a flaw in the Linux kernel's llc_alloc_frame() function where it reserved link-layer headroom based on the device type, which was insufficient for stacked Ethernet devices like VLANs. VLAN devices add a VLAN header before the lower device's Ethernet header, causing LLC responses to potentially underflow skb headroom in eth_header(). The vulnerability was resolved by using LL_RESERVED_SPACE() to correctly account for the actual headroom requirements of the device, maintaining the existing device-type checks.

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 10:53 UTC

Technical details

References

Community reviews

Related threats