CVE-2026-123492
SiYuan before 3.8.9 contains a nil pointer dereference vulnerability in privateCacheMiddleware that allows authenticated attackers to crash
CVSS
4.9
Medio
EPSS
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KEV
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Exploit Today
0
0-100
Publicado: 6 nov 2026 · Última mod.: 6 nov 2026 · CWE-476
Sin historial EPSS suficiente todavía.
SiYuan before 3.8.9 contains a nil pointer dereference vulnerability in privateCacheMiddleware that allows authenticated attackers to crash the kernel by reading nonexistent MCP resources. Attackers with a valid API token can send a resources/read request in an initialized MCP session, causing a panic that terminates the kernel process and interrupts service.
CVECVSSEPSSKEVRExplotTítuloVis.
CVE-2026-870457.5 ALT—
——0The HTTP/2 server in subsys/net/lib/http/http_server_http2.c clears the connection's stream binding at the start of every frame. handle_http_frame_header() executed client->current_stream = NULL unconditionally, but a CONTINUATION frame does not open a new stream and enter_http_frame_continuation_state() never re-bound one, so the rest of the header block was processed with client->current_stream unset. Two paths then write through the NULL pointer. A request for an unregistered resource, or a method the matched resource does not support, is answered by send_http2_404() or send_http2_405(), and both call send_headers_frame(), which unconditionally sets client->current_stream->headers_sent = true. A POST, PUT or PATCH to a registered dynamic resource reaches handle_http2_dynamic_resource(), which unlike its siblings (handle_http2_static_resource(), dynamic_get_del_opts_req_v2(), dynamic_post_put_req_v2()) had no client->current_stream == NULL guard, and stores through the pointer with client->current_stream->current_detail = dynamic_detail.
Any peer that can reach the server can trigger this without authentication or prior state. A single stray CONTINUATION frame with END_HEADERS set, sent right after the client preface and requesting any unregistered path, is enough, because nothing rejected a CONTINUATION that no HEADERS frame had opened. A legitimate split header block (a HEADERS frame with END_HEADERS clear whose payload ends on a header-field boundary, then a CONTINUATION with END_HEADERS set) reaches the same state. The in-tree test test_http2_post_headers_with_continuation() did not catch this because it splits the header block mid field, which takes the handle_incomplete_http_header() shortcut that keeps the stream bound.
The result is a write to a fixed low address (a small offset into struct http2_stream_ctx), which faults on mainstream targets (flash/vector-table region on Cortex-M, or a trap under MPU/MMU null-pointer detection), and the default fatal-error handler halts the system. Impact is an unauthenticated, remotely triggerable denial of service against any device running the HTTP/2 server: the 404 path needs no particular resource to be registered, and HTTP/2 is built into CONFIG_HTTP_SERVER with cleartext h2c accepted, so TLS does not prevent it. Neither the target address nor the written value is attacker-controlled, so there is no confidentiality or integrity impact. Applications built without CONFIG_HTTP_SERVER are not affected.12hCVE-2026-69025—3.4%
——1In the Exynos NPU driver, improper validation of user input in the ioctl handler can lead to an out-of-bounds write, which causes a denial of service6hCVE-2026-48174—6.4%
——2In the NR RRC component, improper handling of messages before authentication triggers a data abort, which leads to a denial‑of‑service condition.6hCVE-2026-121522—1.7%
——1In BuildKit versions v0.26.0 through v0.34.1, a specific build definition that resolves metadata for the same Git source reference twice can cause the BuildKit daemon to panic and crash, interrupting builds handled by that daemon. The issue is fixed in v0.34.2.5hCVE-2026-1209557.5 ALT29.8%
——9The GridFS file download API in the MongoDB C Driver does not check the result of an internal operation under certain error conditions during file retrieval. This can cause the process to terminate when stream operations continue. A user who can influence file download parameters can trigger this condition, which may result in service unavailability for applications using the affected API.3dCVE-2026-1152976.5 MED22.5%
——7NULL Pointer Dereference (CWE-476) in the AMQP protocol parser in Packetbeat can lead to denial of service via specially crafted network traffic. An unauthenticated attacker who can send traffic on a network segment that Packetbeat monitors for AMQP can cause a Go runtime panic that terminates the Packetbeat process. A single crafted packet is sufficient. No AMQP authentication is necessary. While Packetbeat is not running, it does not collect network telemetry.3d