CVE-2026-98703: Linux kernel · wifi: mac80211: minstrel_ht: validate fixed rate index
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 28 Oct 2026, 01:28 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
Exploitation evidence
Disclosed: evidence found.
CVE published 18 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: wifi: mac80211: minstrel_ht: validate fixed rate index The fixed_rate_idx debugfs file is a plain u32 attribute, so any value can be written to it. minstrel_ht_update_stats() then copies the value into mi->max_tp_rate[] and mi->max_prob_rate, and minstrel_ht_set_rate() uses MI_RATE_GROUP()/MI_RATE_IDX() to index minstrel_mcs_groups[] (42 entries) and mi->groups[].rates[] (10 entries) with it. Writing e.g. 65535 selects group 4095 and rate index 15, far outside both arrays. The out-of-bounds entries are dereferenced and updated as struct minstrel_rate_stats (retry counts, etc.), so the invalid index corrupts adjacent kernel memory. With CONFIG_UBSAN_BOUNDS the access is reported as an array-index-out-of-bounds in minstrel_ht_set_rate(). Only a valid group/rate pair, or U32_MAX to disable fixed rate processing, can be used safely, so reject any other value when the debugfs file is written. The file is only reachable through a root-only debugfs mount, so this is not a privilege boundary. The out-of-bounds access is still a bug that must not be reachable through a writable debugfs attribute.
References
- ubuntu.com/security/CVE-2026-98703 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-98703 (opens in a new tab)
- git.kernel.org/stable/c/43082d604a9937b94ceb2e484403956d0f363324 (opens in a new tab)
- git.kernel.org/stable/c/15fb9e3cea55fbc378261ce35a32b0f8828f0000 (opens in a new tab)
- git.kernel.org/stable/c/f8ab6ae1fa360b0191252677f41e781dcb0ffe6e (opens in a new tab)
- git.kernel.org/stable/c/42aa9feb27b600809414a3c6b0c650bafba542a9 (opens in a new tab)