CVE-2026-98075: Linux kernel · bpf: reject BPF_PSEUDO_FUNC reference to the main program
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 6% 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.
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: reject BPF_PSEUDO_FUNC reference to the main program fixups.c:jit_subprogs() rewrites BPF_PSEUDO_FUNC loads to contain real function addresses. This function is invoked from bpf_jit_subprogs() only when env->subprog_cnt > 1. Meaning that for any program like below: int main(void *ctx) { void *ptr = main; ... bpf_timer_set_callback(..., ptr); ... } The 'ptr' won't be ever converted to contain an address. In combination with e.g. bpf_timer_set_callback() this would lead to a function call at a bogus address. Instead of complicating the implementation, just assume that no useful program needs main to be a sync or async callback and reject BPF_PSEUDO_FUNC loads for the main subprogram.
References
- ubuntu.com/security/CVE-2026-98075 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-98075 (opens in a new tab)
- git.kernel.org/stable/c/118212417ba0120d99f84154799f8880f07411f4 (opens in a new tab)
- git.kernel.org/stable/c/374b2c5561db80fcdd7cdce44af37a49416f61c7 (opens in a new tab)
- git.kernel.org/stable/c/92f0bd0e2b632c6565ac2214a4d7d2ed37e5b9f6 (opens in a new tab)
- git.kernel.org/stable/c/d6c39774ae093c9f7009cc4ae918f18fc1af7ae7 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-98075 (opens in a new tab)
- git.kernel.org/stable/c/314c8caa9cb64ad60c5b969fe9a3e2dcdccf156f (opens in a new tab)
- git.kernel.org/stable/c/8cb75f7ada25b1cf25f2f74dec3ba649b9064a09 (opens in a new tab)
- git.kernel.org/stable/c/c74750dca96f40a1adb9d334f5a3152f44b270c3 (opens in a new tab)