CVE-2026-98063: Linux kernel · bpf: Fix NULL-ptr-deref in btf_var_show()
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 26 Oct 2026, 12:55 UTC
Rated by Threat Radar · 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.
Exploitation 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
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available that addresses the NULL pointer dereference in btf_var_show() by adding appropriate checks and resolving the variable's type safely. Users should apply the official kernel updates for the affected linux-hwe-edge versions to remediate this issue.
Description
A NULL pointer dereference vulnerability in the Linux kernel's BPF subsystem was fixed in the btf_var_show() function. The function btf_var_show() unconditionally calls btf_type_id_resolve(), which dereferences a NULL pointer in certain base BTF contexts, causing a kernel crash. This issue affects specific linux-hwe-edge kernel versions and was resolved by adding a check similar to btf_modifier_show().
References
- ubuntu.com/security/CVE-2026-98063 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-98063 (opens in a new tab)
- git.kernel.org/stable/c/5403a383f52fc0905703b488f7c3db4b2447dc58 (opens in a new tab)
- git.kernel.org/stable/c/e472ae0d97865e2021ee668a13eab64013aebf23 (opens in a new tab)
- git.kernel.org/stable/c/ca086264e98108b44fdf53971033811a48defe2b (opens in a new tab)
- git.kernel.org/stable/c/ea383b3ea56979ce54c8aa88e6ec67164986c401 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-98063 (opens in a new tab)
- git.kernel.org/stable/c/5756450c9a702da0efb4a993d0a6766b965736f3 (opens in a new tab)
- git.kernel.org/stable/c/aec0a9c1579eb9edf534960be592d09481bd7ac3 (opens in a new tab)
- git.kernel.org/stable/c/e0d6a06171633d3ee3f7a39b57e5c845fb2b79f2 (opens in a new tab)
- git.kernel.org/stable/c/e83fcbe3b5d4a1ffb0569bb7c280358065c6017a (opens in a new tab)