# CVE-2026-98935: rtc: dev: zero-initialize struct rtc_wkalrm to prevent information leak


- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Fix available:** Yes
- **Published:** 23 Oct 2026
- **Updated:** 23 Oct 2026
- **Also known as:** AZL-110723, BELL-CVE-2026-98935, DEBIAN-CVE-2026-98935, GHSA-p9j5-gjf3-cch6, UBUNTU-CVE-2026-98935

## What is CVE-2026-98935?

CVE-2026-98935 is a vulnerability in Linux, published on 23 Oct 2026. 

### Official description

In the Linux kernel, the following vulnerability has been resolved:

rtc: dev: zero-initialize struct rtc_wkalrm to prevent information leak

The struct rtc_wkalrm has padding holes after the 'pending' member.
When returned to userspace via the RTC_WKALRM_RD ioctl, uninitialized
kernel stack data residing in these holes may be leaked.

Zero-initialize the struct at declaration to eliminate this information
leak risk.

Fixes smatch warnings:
- drivers/rtc/dev.c:392 rtc_dev_ioctl() warn: check that 'alarm' doesn't
  leak information (struct has a hole after 'pending')

## Which versions are affected by CVE-2026-98935?


## How do I fix CVE-2026-98935?

Upgrade to a fixed version.

## Is CVE-2026-98935 being exploited?

There is no known exploitation of CVE-2026-98935 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98935 and fix it if it is affected.

What it is: CVE-2026-98935 is a vulnerability in Linux, published on 23 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-98935 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-98935/ (Markdown: https://insights.sbomify.com/CVE-2026-98935/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98935
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98935
- OSV: https://osv.dev/vulnerability/CVE-2026-98935

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98935/
Summaries are generated and may contain mistakes; the official description above is the record.