VulnerabilityPublished 18 Oct 2026

CVE-2026-98625: Linux kernel · netfilter: flowtable: publish HW_DEAD after worker is done

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in f26652e99f519e6bd34f8a9b48fbb33c603585f2 : patch Linux kernel soon.

Data as of 26 Oct 2026, 14:05 UTC

Severity

High

Rated High by Threat Radar's AI analysis · 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 f26652e99f519e6bd34f8a9b48fbb33c603585f2, f92e8f39726ba68a7c42c6b7566be687c8161579, e20701843032c438f879066a77ea85e361c6b999 +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 ≥ 2c8897953f3b2ff5498f3f275708a742bfcdbc24, < f26652e99f519e6bd34f8a9b48fbb33c603585f2	Fixed in f26652e99f519e6bd34f8a9b48fbb33c603585f2
LinuxLinux	Affected ≥ 2c8897953f3b2ff5498f3f275708a742bfcdbc24, < f92e8f39726ba68a7c42c6b7566be687c8161579	Fixed in f92e8f39726ba68a7c42c6b7566be687c8161579
LinuxLinux	Affected ≥ 2c8897953f3b2ff5498f3f275708a742bfcdbc24, < e20701843032c438f879066a77ea85e361c6b999	Fixed in e20701843032c438f879066a77ea85e361c6b999
LinuxLinux	Affected ≥ 2c8897953f3b2ff5498f3f275708a742bfcdbc24, < d644b23afe1ef509c9961a6d84a093c2587edf02	Fixed in d644b23afe1ef509c9961a6d84a093c2587edf02
LinuxLinux	Affected ≥ 2c8897953f3b2ff5498f3f275708a742bfcdbc24, < b4f0f05dfbe836a171bff261f17d098a4d5461ea	Fixed in b4f0f05dfbe836a171bff261f17d098a4d5461ea
LinuxLinux	Affected ≥ 2c8897953f3b2ff5498f3f275708a742bfcdbc24, < b0ef9450e93f2adeb77593db14c2ac7c6c8f5060	Fixed in b0ef9450e93f2adeb77593db14c2ac7c6c8f5060

AI-suggested

A fix is available and has been applied in several Linux kernel commits following version 5.7. Users and administrators should update their Linux kernel to a version that includes these fixes to mitigate the vulnerability.

Description

A use-after-free vulnerability was identified and resolved in the Linux kernel's netfilter flowtable component. The issue arises from improper ordering of state flags (HW_DEAD and HW_PENDING) during flow offload worker execution, which can lead to premature freeing of flow objects while still in use. This flaw affects Linux kernel version 5.7 and has been fixed in subsequent commits.

Impact

The vulnerability can lead to a use-after-free condition in the Linux kernel netfilter flowtable subsystem. This can cause kernel memory corruption, potentially leading to system instability, crashes, or escalation of privileges if exploited. However, no known exploits in the wild have been reported.

Summary

The vulnerability in the Linux kernel's netfilter flowtable involves the premature publication of the HW_DEAD flag before the worker clears the HW_PENDING flag. This improper ordering allows a concurrent garbage collection pass to remove and schedule the flow object for RCU freeing while the offload worker still references it without holding an RCU read lock or a flow reference. If the worker is preempted after publishing HW_DEAD, the flow can be freed before the worker clears HW_PENDING, resulting in a use-after-free condition. The fix moves the HW_DEAD publication to the worker epilogue after clearing HW_PENDING, ensuring proper synchronization and preventing premature freeing.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 10:08 UTC

Technical details

References

Community reviews

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