# CVE-2026-10684: Out-of-bounds read in coredump shell when printing stored-dump target code

> An out-of-bounds read in Zephyr's coredump shell allows local attackers to disclose memory or crash the system by corrupting stored dump headers.

- **Severity:** Low 3.0 (`CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 29 Jul 2026
- **Updated:** 31 Aug 2026
- **Also known as:** GHSA-9fw2-4429-49q8

## What is CVE-2026-10684?

CVE-2026-10684 is a low-severity vulnerability in zephyrproject zephyr, published on 29 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In subsys/debug/coredump/coredump_shell.c, print_coredump_hdr() used the 16-bit tgt_code field of a stored Zephyr coredump header directly as an index into coredump_target_code2str[], a fixed 7-element array of string pointers, with no bounds check.

A stored coredump whose tgt_code is >= 7 causes an out-of-bounds read of a char* up to ~64K entries past the array; that value is passed as the %s argument to shell_print, which dereferences and walks it as a string. The result is either disclosure of device memory contents to the shell user or a crash when the out-of-bounds pointer is unmapped.

The defect is reached via the coredump print shell command (cmd_coredump_print_stored_dump -> pretty_print_coredump -> parse_and_print_coredump -> print_coredump_hdr). The tgt_code field is device-generated and in-range during normal crash handling, so triggering requires local shell access plus the ability to stage or corrupt the stored coredump in the flash/in-memory backend.

Introduced in v4.2.0 (commit 13abd7fe730) and present through v4.4.0; fixed by clamping out-of-range codes to the 'unknown' (index 0) entry.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-10684?


## How do I fix CVE-2026-10684?

No fix has been published for CVE-2026-10684 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-10684 being exploited?

There is no known exploitation of CVE-2026-10684 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-10684 and fix it if it is affected.

What it is: CVE-2026-10684 is a low-severity vulnerability in zephyrproject zephyr, published on 29 Jul 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-2026-10684 in the wild and no public exploit code.

Affected product: zephyrproject zephyr. 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-2026-10684/ (Markdown: https://insights.sbomify.com/CVE-2026-10684/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-10684
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-10684
- OSV: https://osv.dev/vulnerability/CVE-2026-10684

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-10684/
Summaries are generated and may contain mistakes; the official description above is the record.