# CVE-2026-43289: kexec: derive purgatory entry from symbol

> A flaw in the Linux kernel kexec subsystem can trigger a kernel warning and potential crash when loading purgatory images with overlapping executable sections.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 8 May 2026
- **Updated:** 23 May 2026
- **Also known as:** BELL-CVE-2026-43289, DEBIAN-CVE-2026-43289, GHSA-3xcp-xr96-v535, ROOT-OS-DEBIAN-11-CVE-2026-43289, ROOT-OS-UBUNTU-2204-CVE-2026-43289, ROOT-OS-UBUNTU-2404-CVE-2026-43289, UBUNTU-CVE-2026-43289

## What is CVE-2026-43289?

CVE-2026-43289 is a medium-severity denial of service vulnerability in Linux kernel, published on 8 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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

kexec: derive purgatory entry from symbol

kexec_load_purgatory() derives image->start by locating e_entry inside an
SHF_EXECINSTR section.  If the purgatory object contains multiple
executable sections with overlapping sh_addr, the entrypoint check can
match more than once and trigger a WARN.

Derive the entry section from the purgatory_start symbol when present and
compute image->start from its final placement.  Keep the existing e_entry
fallback for purgatories that do not expose the symbol.

WARNING: kernel/kexec_file.c:1009 at kexec_load_purgatory+0x395/0x3c0, CPU#10: kexec/1784
Call Trace:
 <TASK>
 bzImage64_load+0x133/0xa00
 __do_sys_kexec_file_load+0x2b3/0x5c0
 do_syscall_64+0x81/0x610
 entry_SYSCALL_64_after_hwframe+0x76/0x7e

[me@linux.beauty: move helper to avoid forward declaration, per Baoquan]

## Which versions are affected by CVE-2026-43289?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-43289?

Apply the vendor's patch.

## Is CVE-2026-43289 being exploited?

There is no known exploitation of CVE-2026-43289 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-43289 and fix it if it is affected.

What it is: CVE-2026-43289 is a medium-severity denial of service vulnerability in Linux kernel, published on 8 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-43289 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2026-43289/ (Markdown: https://insights.sbomify.com/CVE-2026-43289/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-43289
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-43289
- OSV: https://osv.dev/vulnerability/CVE-2026-43289

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-43289/
Summaries are generated and may contain mistakes; the official description above is the record.
