CVE-2026-98201: Linux kernel · Input: zero ff_effect before compat copy in input_ff_effect_from_user
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 28 Oct 2026, 01:27 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
Exploitation evidence
Disclosed: evidence found.
CVE published 6 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
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: Input: zero ff_effect before compat copy in input_ff_effect_from_user In the compat path input_ff_effect_from_user() aliases the caller's native struct ff_effect with the smaller struct ff_effect_compat and copies only the compat sized prefix: compat_effect = (struct ff_effect_compat *)effect; if (copy_from_user(compat_effect, buffer, sizeof(struct ff_effect_compat))) The tail of the native structure is never written. Callers pass an uninitialized on-stack object, for example evdev_do_ioctl() for EVIOCSFF, so those bytes keep their previous stack contents. input_ff_upload() then stores the full native structure in ff->effects[id], from where a uinput based force feedback daemon can read it back via UI_BEGIN_FF_UPLOAD, disclosing kernel stack memory to userspace. Zero the effect before the compat copy.
References
- ubuntu.com/security/CVE-2026-98201 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-98201 (opens in a new tab)
- git.kernel.org/linus/f84819ef8d66931ee3998fee3c4f03230f4cb6cc (opens in a new tab)
- git.kernel.org/stable/c/0d05b43b55d4784a42ce8fb318175f8ad7d9af5a (opens in a new tab)
- git.kernel.org/stable/c/6c26681c5668c973bd0e951407d670ac60d9cd66 (opens in a new tab)
- git.kernel.org/stable/c/b878720e8bcaa4cf7163a5081f904dd6baf11b2c (opens in a new tab)
- git.kernel.org/stable/c/c5e573bb095d502be7cbbaa99c26a20984111c6d (opens in a new tab)
- git.kernel.org/stable/c/ec174c2ab1abb76b20fa167c6db848c3d97aa838 (opens in a new tab)
- git.kernel.org/stable/c/ed0406e490f48ed180df140fe2a81be26bccb1a9 (opens in a new tab)
- git.kernel.org/stable/c/ed0905fda39682d3da7937184397d3276abbffa8 (opens in a new tab)
- git.kernel.org/stable/c/f84819ef8d66931ee3998fee3c4f03230f4cb6cc (opens in a new tab)