CVE-2026-10684

Received Received - Intake

Out-of-Bounds Read in Zephyr RTOS Coredump Shell

Publication date: 2026-07-29

Last updated on: 2026-07-29

Assigner: Zephyr Project

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.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-07-29

Last Modified

2026-07-29

Generated

2026-07-30

AI Q&A

2026-07-30

EPSS Evaluated

N/A

NVD

CVE-2026-10684

Affected Vendors & Products

Vendor	Product	Version / Range
zephyr_project	zephyr	From 4.2.0 (inc) to 4.4.0 (inc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-125	The product reads data past the end, or before the beginning, of the intended buffer.

Attack-Flow Graph

Executive Summary

This vulnerability is an out-of-bounds read in the Zephyr RTOS coredump shell command. It occurs when the tgt_code field in a stored coredump header is used as an index into a fixed-size array without bounds checking. If tgt_code is 7 or higher, it reads beyond the array, potentially exposing device memory or causing a crash.

Detection Guidance

This vulnerability requires local shell access and a corrupted or staged coredump file. Check for unauthorized shell access or unexpected coredump files in flash/in-memory storage. No direct network detection is possible.

Impact Analysis

An attacker with local shell access could exploit this to read sensitive device memory or crash the system. This requires the ability to stage or corrupt a stored coredump in flash or memory. Normal crash handling does not trigger the flaw.

Mitigation Strategies

Apply the vendor fix by updating to a version where out-of-range tgt_code values are clamped to 'unknown'. Ensure only authorized users have shell access to prevent staging corrupted coredumps.

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