CVE-2026-10648

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Source

https://cve.org/CVERecord?id=CVE-2026-10648

Import Source

https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-10648.json

JSON Data

https://api.osv.dev/v1/vulns/CVE-2026-10648

Aliases

GHSA-j64f-h3ww-f32c

Published

2026-06-29T22:51:27Z

Modified

2026-10-21T08:41:12Z

Severity

6.2 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator

Summary

NULL-pointer dereference in MCUmgr serial/console SMP transport on buffer-pool exhaustion

Details

mcumgr_serial_process_frag() in subsys/mgmt/mcumgr/transport/src/serial_util.c calls net_buf_reset() on the result of smp_packet_alloc() before checking it for NULL. smp_packet_alloc() uses net_buf_alloc(K_NO_WAIT) against the shared MCUmgr packet pool (CONFIG_MCUMGR_TRANSPORT_NETBUF_COUNT, default 4), which returns NULL when the pool is exhausted. In default builds the __ASSERT_NO_MSG in net_buf_reset is a no-op, so net_buf_simple_reset writes through the NULL pointer (buf->len = 0; buf->data = buf->__buf), causing a fault/crash.

The fragment data reaches this code from attacker-controlled bytes on the MCUmgr serial/UART/shell-console transports (smp_uart.c, smp_raw_uart.c, smp_shell.c), and a fresh buffer is allocated at the start of essentially every new packet. An attacker on the serial/console link can flood the transport to drive the 4-entry buffer pool to exhaustion and induce the NULL dereference, crashing the device (denial of service).

The defect was introduced after the original MCUmgr rework and shipped in Zephyr v4.4.0. The fix moves the NULL check ahead of net_buf_reset.

Database specific

{
    "cna_assigner":  "zephyr",
    "cwe_ids":  [
        "CWE-476"
    ],
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/10xxx/CVE-2026-10648.json"
}

References

Affected packages

Git / github.com/zephyrproject-rtos/zephyr

Affected ranges

Type

GIT

Repo

https://github.com/zephyrproject-rtos/zephyr

Events

Introduced

684c9e8f32e4373a21098559f748f06915f950c9

Fixed

1f6485eca25431b5ff27ce9a754218c9e559bbbb

Fixed

6f363ec6f7fd6ae9ed7ca2ae66fd9c82dce31c59

Database specific

Show details

{
    "extracted_events":  [
        {
            "range":  [
                {
                    "introduced":  "4.4.0"
                },
                {
                    "fixed":  "4.4.1"
                }
            ],
            "source":  "AFFECTED_FIELD",
            "strategy":  "StandardRange"
        },
        {
            "range":  [
                {
                    "fixed":  "6f363ec6f7fd6ae9ed7ca2ae66fd9c82dce31c59"
                }
            ],
            "source":  "REFERENCES_COMMIT"
        }
    ]
}

Affected versions

v4.*

v4.4.0

v4.4.1-rc1

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-10648.json"

vanir_signatures

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        "id":  "CVE-2026-10648-10b0c8aa",
        "signature_type":  "Function",
        "signature_version":  "v1",
        "source":  "https://github.com/zephyrproject-rtos/zephyr/commit/6f363ec6f7fd6ae9ed7ca2ae66fd9c82dce31c59",
        "target":  {
            "file":  "subsys/mgmt/mcumgr/transport/src/serial_util.c",
            "function":  "mcumgr_serial_process_frag"
        }
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vanir_signatures_modified

"2026-10-21T08:41:12Z"