CVE-2026-89513: Linux kernel · RISC-V: KVM: Fix PMU event info array size overflow
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 8.8 High.
Data as of 26 Oct 2026, 14:05 UTC
- 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.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 11 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 properly handles the PMU event info array size calculation and memory allocation to prevent overflow and out-of-bounds access. Users should apply the official Linux kernel patches that address CVE-2026-89513. There are no vendor advisories indicating no action is required or that the issue is already mitigated. Since this is not a cloud service, remediation depends on applying the kernel updates.
Description
A vulnerability in the Linux kernel's RISC-V KVM implementation allows an out-of-bounds read and write due to an integer overflow when handling PMU event info arrays. This occurs when a guest provides a large num_events value causing allocation of insufficient memory but looping over the original large count, leading to memory corruption. The issue has been fixed by properly handling size calculations and allocation.
References
- nvd.nist.gov/vuln/detail/CVE-2026-89513 (opens in a new tab)
- git.kernel.org/stable/c/735bc20c24187ca419c9d5e63860a54b91be34bd (opens in a new tab)
- git.kernel.org/stable/c/82088f88c96b99c27a974d09b02c2b133262fadf (opens in a new tab)
- ubuntu.com/security/CVE-2026-89513 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-89513 (opens in a new tab)
- git.kernel.org/linus/735bc20c24187ca419c9d5e63860a54b91be34bd (opens in a new tab)