CVE-2026-98950: Linux kernel · flow_dissector: avoid u16 truncation of hlen in bpf_flow_dissect()
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in f202578efc738b883cfa04889eb97328914265a7 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 17:30 UTC
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 7% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in f202578efc738b883cfa04889eb97328914265a7, cc18eb0e9941162c03f03f411ed7f6c339d91fa0, c44c02c930c6583b235a1937c69ff716c4bb4514 +2
Exploitation evidence
Disclosed: evidence found.
CVE published 23 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.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in– |
AI-suggested
This vulnerability has been fixed in Linux kernel versions following 4.20, as indicated by multiple commits. Users and administrators should update to a Linux kernel version that includes these fixes to mitigate the issue. No additional mitigation steps are specified or required beyond applying the official patches.
Description
CVE-2026-98950 is a vulnerability in the Linux kernel's flow_dissector component where a 16-bit truncation error occurs in the bpf_flow_dissect() function when handling the hlen value. This truncation can cause offsets to be incorrectly set to zero even if the BPF program returns valid values. The issue was fixed by capping hlen to the maximum value of a 16-bit unsigned integer before clamping. The vulnerability affects Linux kernel version 4.20 and has been resolved in subsequent commits.
References
- git.kernel.org/stable/c/c44c02c930c6583b235a1937c69ff716c4bb4514 (opens in a new tab)
- git.kernel.org/stable/c/3fb5ad2951a6df92c98f4f06cd70f20c50a2eb2a (opens in a new tab)
- git.kernel.org/stable/c/cc18eb0e9941162c03f03f411ed7f6c339d91fa0 (opens in a new tab)
- git.kernel.org/stable/c/61b43a51a55929ec040bee3ea51af2121b956d05 (opens in a new tab)
- git.kernel.org/stable/c/f202578efc738b883cfa04889eb97328914265a7 (opens in a new tab)