CVE-2026-98044: Linux kernel · bpf: Reject legacy packet loads from callbacks
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 26 Oct 2026, 14:05 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 5% 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
The vulnerability has been resolved by rejecting legacy packet-load instructions from callbacks in the Linux kernel BPF verifier. Users should update to a fixed kernel version that includes this patch. Since the legacy instructions are deprecated and rejected from callbacks, avoiding their use in callbacks also mitigates the issue. No additional action is required beyond applying the official fix when available.
Description
A vulnerability in the Linux kernel's BPF subsystem involving legacy packet load instructions from callbacks has been resolved. The issue arises when the verifier encounters legacy BPF_LD_ABS or BPF_LD_IND instructions in callbacks, causing a verifier bug and resulting in a program load failure with an -EFAULT error. The fix rejects these deprecated legacy packet-load instructions from callbacks to prevent this verifier error. Ordinary uses of these instructions outside callbacks remain supported.
References
- ubuntu.com/security/CVE-2026-98044 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-98044 (opens in a new tab)
- git.kernel.org/stable/c/3484a99303912db62428494a9061212049027e57 (opens in a new tab)
- git.kernel.org/stable/c/bc489c0c9b8c86bd7fac42cfd1bb152f042fca56 (opens in a new tab)
- git.kernel.org/stable/c/e7d28823c662128caae63f14e16bd394916c139b (opens in a new tab)