CVE-2026-15892
MediumCVSS 5.3Exploitation Probability (EPSS)
Low risk20th percentile - higher than 20% of all known CVEs
Summary
In CVE-2026-15892, the mcumgr settings-management group handlers settings_mgmt_read(), settings_mgmt_write(), and settings_mgmt_delete() allocate a key_name buffer (and a data buffer for read) via k_malloc() when CONFIG_MCUMGR_GRP_SETTINGS_BUFFER_TYPE_HEAP is enabled. When CONFIG_MCUMGR_GRP_SETTINGS_ACCESS_HOOK is also enabled and the application access hook rejects a request by returning MGMT_CB_ERROR_RC, the handler executes return ret_rc directly, bypassing the end: label and k_free(), leaking the heap allocation on every rejected request.
Risk Assessment
An attacker can send settings read/write/delete commands over the unauthenticated SMP transport (Bluetooth LE, UART, or UDP) that the hook rejects, monotonically exhausting the kernel heap until k_malloc() fails. This causes a denial of service for mcumgr and any other heap consumer on the device; the impact is availability-only, with no memory corruption or information disclosure.
Recommendation
Update to a version containing the fix that ensures the allocation is freed before returning the access hook error. If updating is not possible, consider disabling CONFIG_MCUMGR_GRP_SETTINGS_ACCESS_HOOK or changing the hook to not return MGMT_CB_ERROR_RC, and restrict access to the SMP transport.
Related vulnerabilities
- CVE-2026-123614Critical
imgproxy from 4.0.0 before 4.0.16 contains an integer overflow in the ICO loader that allows remote attackers to trigger a heap buffer overflow via a crafted data_size value. Attackers can submit a crafted ICO image whose data_size wraps the allocation in vips/icoload.c, corrupting heap memory to crash the process or achieve code execution.
- CVE-2026-123551Critical
OpenAM from 14.0.0 before 16.1.4 contains an information disclosure vulnerability that allows unauthenticated attackers to read live session tokens from the notification WebSocket. Attackers can bypass the agent-only check through an unvalidated internal forward on legacy Liberty ID-FF endpoints, collecting iPlanetDirectoryPro tokens to hijack user and administrator sessions.
- CVE-2026-123550Critical
OpenAM before 16.1.4 contains an authentication bypass vulnerability in its SAML v2.0 service provider that accepts unsigned assertions on the ECP (PAOS) and HTTP-Artifact bindings when WantAssertionsSigned is false. Unauthenticated remote attackers can submit forged assertions to obtain sessions as any mapped user, including administrators, and hijack single sign-on to dependent applications.
- CVE-2026-123549Critical
OpenAM before 16.1.4 fails to enforce the Valid Creation Attributes list during self-registration, allowing anonymous attackers to set restricted attributes including group membership. Attackers can register through the legacy self-service REST endpoint or User Self-Service flow to join administrative groups and gain full administrative control of OpenAM.
- CVE-2026-124060Critical
A vulnerability was detected in TOTOLINK CA300-PoE version 6.2c.884 in the UploadCustomModule function of the file /cgi-bin/cstecgi.cgi. Manipulation of the File argument results in a buffer overflow. The attack can be launched remotely, and the exploit is now public and may be used.
- CVE-2026-124059Critical
A security vulnerability has been detected in TOTOLINK CA300-PoE 6.2c.884. The function setWiFiWdsAddConfig in the file /cgi-bin/cstecgi.cgi is affected, where manipulation of the ApCliKeyStr argument leads to a buffer overflow. The attack may be initiated remotely, and the exploit has been disclosed publicly and may be used.
- CVE-2026-124058Critical
A weakness has been identified in TOTOLINK CA300-PoE 6.2c.884. The function setWiFiRepeaterConfig in the file /cgi-bin/cstecgi.cgi is affected, where manipulation of the ApCliKeyStr argument can lead to a buffer overflow. The attack can be launched remotely, and the exploit has been made available to the public and could be used for attacks.
- CVE-2026-124057Critical
A security flaw has been discovered in TOTOLINK CA300-PoE 6.2c.884. This impacts the function setWiFiMultipleConfig of the file /cgi-bin/cstecgi.cgi. Manipulation of the argument Key1Str1 results in a buffer overflow. The attack can be initiated remotely. The exploit has been released to the public and may be used for attacks.
- CVE-2026-123966Critical
A vulnerability was found in Tenda AC19 version 16.03.10.07 in the saveParentControlInfo function of the /goform/saveParentControlInfo file. Manipulating the deviceId argument causes a heap-based buffer overflow. The attack can be carried out remotely, and the exploit has been publicly disclosed.
- CVE-2026-120984Critical
A flaw was found in the Keycloak server's client management component. When a client is created or imported with authorization services enabled, the system fails to properly clear an internal session attribute used during setup. An authenticated attacker with client management permissions can bypass security controls and upload a malicious JavaScript policy that executes on the server.
Original NVD description (English source)
The mcumgr SMP settings-management group handlers settings_mgmt_read(), settings_mgmt_write(), and settings_mgmt_delete() in subsys/mgmt/mcumgr/grp/settings_mgmt/src/settings_mgmt.c allocate a key_name buffer (and, for read, a data buffer) via k_malloc() when CONFIG_MCUMGR_GRP_SETTINGS_BUFFER_TYPE_HEAP is enabled, relying on the end: label to k_free() them. When CONFIG_MCUMGR_GRP_SETTINGS_ACCESS_HOOK is also enabled and the application access hook rejects a request by returning status MGMT_CB_ERROR_RC, the handler executed return ret_rc; directly, bypassing end: and leaking the heap allocation on every rejected request. The settings handlers are reachable over the unauthenticated SMP transport (Bluetooth LE, UART, or UDP, depending on product configuration). The access hook is the mechanism applications use to deny unauthorized settings access, and MGMT_CB_ERROR_RC is a common rejection style, so an attacker who can send settings read/write/delete commands that the hook rejects triggers a heap leak on each attempt. Because the leaked memory is never reclaimed until reboot, a sustained stream of rejected requests monotonically exhausts the kernel heap until k_malloc() fails, denying mcumgr service and impacting any other heap consumer on the device — a denial of service. The impact is availability-only; there is no memory corruption or information disclosure. Only configurations that select the heap buffer type, enable the access hook, and register a hook that returns MGMT_CB_ERROR_RC are affected (the default stack buffer type cannot leak).
Vulnerability data from NVD (NIST) · CISA KEV · EPSS