CVE-2026-98023: Linux kernel · vxlan: reject dynamic fdb entries that reference a nexthop id
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.8 High · fixed in c8f29af91e0830fdabc9aa1eb1a0f898ce1bc603 : patch Linux kernel soon.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in c8f29af91e0830fdabc9aa1eb1a0f898ce1bc603, b2a8e165ddb6cd72176890b2954c52b0f6dbce1a, 53359916ceb649b7e6947c8c2f669368a41c1354 +5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Sep 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
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AI-suggested
A fix is available and has been applied in the Linux kernel. Systems running the affected version (5.8) should be updated to a fixed kernel version containing the commits listed in the established facts. No additional mitigation is required once patched.
Description
CVE-2026-98023 is a vulnerability in the Linux kernel's VXLAN driver where dynamic forwarding database (FDB) entries referencing a nexthop ID were not properly rejected. This flaw could lead to list corruption and use-after-free bugs due to race conditions when multiple VXLAN devices share the same FDB nexthop list. The issue has been fixed by rejecting such invalid dynamic FDB entries and ensuring proper locking during list mutations.
References
- git.kernel.org/stable/c/00c7f4b8144e535ffb931ad45942a1bd1315b882 (opens in a new tab)
- git.kernel.org/stable/c/55a33882808f1402052d53a08ead59aff8af18a1 (opens in a new tab)
- git.kernel.org/stable/c/c8f29af91e0830fdabc9aa1eb1a0f898ce1bc603 (opens in a new tab)
- git.kernel.org/stable/c/b2a8e165ddb6cd72176890b2954c52b0f6dbce1a (opens in a new tab)
- git.kernel.org/stable/c/28f86eec851b7406a4bc6143f82aeba2882d9842 (opens in a new tab)
- git.kernel.org/stable/c/53359916ceb649b7e6947c8c2f669368a41c1354 (opens in a new tab)
- git.kernel.org/stable/c/3fa64d86fc64eda104e3e97721a12a42a2fd2073 (opens in a new tab)
- git.kernel.org/stable/c/98fc57d167446b95b4e719815fe79edef93f8e7a (opens in a new tab)