CVE-2026-123492

SiYuan before 3.8.9 Nil Pointer Dereference DoS via MCP resources/read

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.

CVSS 4.0 · 6.9 Medium EPSS < 1% KEV · Not listed

Vendors

B3log Siyuan

Products

Siyuan Siyuan

CVE-2026-76166

Modcluster-core: mod_cluster advertise listener: unauthenticated dos via crafted multicast datagram

A flaw was found in mod_cluster's AdvertiseListenerImpl (org.jboss.modcluster core module). A single crafted UDP multicast datagram with a valid HTTP status line and a "Server:" header but without the "Date:", "Digest:", and "Sequence:" headers triggers a NullPointerException in verifyDigest() that is not caught by the worker thread's exception handler. This causes the advertise listener thread to terminate permanently. The failure is silent (isListening() continues to return true) and persists until the node is restarted. The crash occurs before the AdvertiseSecurityKey comparison, so deployments with a configured security key are still affected.

CVSS 3.1 · 4.3 Medium EPSS 2.4% KEV · Not listed

Vendors

Redhat

Products

Jboss Enterprise Application Platform Jboss Enterprise Application Platform Expansion Pack Jboss Enterprise Web Server and 4 more

CVE-2026-125231

FFmpeg 4.4 through 9.0.2 NULL Pointer Dereference via adx_decode_header()

FFmpeg 4.4 through 9.0.2 contains a NULL pointer dereference vulnerability in libavcodec/adxdec.c because adx_decode_header() updates the channel layout before validating the sample rate. Attackers can supply a crafted ADX/AAX stream with mid-stream new-extradata side data carrying an invalid sample rate, causing adx_decode() to write through NULL plane pointers and crash the application.

CVSS 4.0 · 6.8 Medium EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125216

FFmpeg through 9.0.2 DPX Encoder NULL Pointer Dereference via encode_gbrp12()

FFmpeg through 9.0.2 contains a NULL pointer dereference vulnerability in libavcodec/dpxenc.c that allows attackers to crash the process via unvalidated bits_per_raw_sample for RGB48 input. Attackers can supply a 12-bit RGB image, such as JPEG 2000, that when transcoded to DPX selects encode_gbrp12() and dereferences NULL plane pointers, causing denial of service.

CVSS 4.0 · 6.8 Medium EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-125215

FFmpeg 7.1 through 9.0.2 NULL Pointer Dereference via ff_dovi_rpu_generate()

FFmpeg 7.1 through 9.0.2 contains a NULL pointer dereference vulnerability in ff_dovi_rpu_generate() in libavcodec/dovi_rpuenc.c that allows attackers to crash applications via crafted Dolby Vision RPU metadata. Attackers can supply streams with default or alternating omitted DM blocks to the dovi_rpu bitstream filter with compression enabled, causing denial of service.

CVSS 4.0 · 5.7 Medium EPSS < 1% KEV · Not listed

Vendors

Ffmpeg

Products

Ffmpeg

CVE-2026-71200

krb5: Unauthenticated KDC NULL pointer dereference KDC DoS via crafted PKINIT pre-auth request

If a KDC is configured to allow PKINIT authentication, an unauthenticated attacker can trigger a null pointer dereference, causing the process to terminate.

CVSS 3.1 · 7.5 High EPSS n/a KEV · Not listed

Vendors

—

Products

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CVE-2026-0401

Null Pointer Dereference Crash Vulnerability in SonicOS

A post-authentication NULL Pointer Dereference vulnerability in SonicOS allows a remote attacker to crash a firewall.

CVSS 3.1 · 4.9 Medium EPSS < 1% KEV · Not listed

Vendors

Sonicwall

Products

Nsa 2700 Nsa 2800 Nsa 3700 and 30 more

CVE-2026-123507

Vikunja 0.24.0 before 2.7.1 Denial of Service via Nil Bucket Filter

Vikunja from 0.24.0 before 2.7.1 contains a nil pointer dereference vulnerability that allows project admins to break project views by saving a filter-mode bucket configuration with a null filter. Because validateProjectViewFilters skips nil entries, every subsequent read of the view panics in kanban and task collection code, returning HTTP 500 to all project members.

CVSS 4.0 · 5.1 Medium EPSS < 1% KEV · Not listed

Vendors

Vikunja

Products

Vikunja

CVE-2026-76492

Cisco Expressway Series Software Hardening Release: October 2026 - NULL Pointer Vulnerabilities

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Expressway Series software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. &nbsp; The vulnerabilities tracked by CVE-2026-76492 are related to issues concerning null pointers that are grouped under the Common Weakness Enumeration (CWE) Base CWE-476.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Cisco

Products

Expressway Series

CVE-2023-4385

Kernel: jfs: null pointer dereference in dbfree()

A NULL pointer dereference flaw was found in dbFree in fs/jfs/jfs_dmap.c in the journaling file system (JFS) in the Linux Kernel. This issue may allow a local attacker to crash the system due to a missing sanity check.

CVSS 3.1 · 5.5 Medium EPSS < 1% KEV · Not listed

Vendors

Linux Redhat

Products

Linux Kernel Enterprise Linux Rhel Els

CVE-2023-3772

Kernel: xfrm: null pointer dereference in xfrm_update_ae_params()

A flaw was found in the Linux kernel’s IP framework for transforming packets (XFRM subsystem). This issue may allow a malicious user with CAP_NET_ADMIN privileges to directly dereference a NULL pointer in xfrm_update_ae_params(), leading to a possible kernel crash and denial of service.

CVSS 3.1 · 5.5 Medium EPSS < 1% KEV · Not listed

Vendors

Debian Fedoraproject Linux and 1 more

Products

Debian Linux Fedora Linux Kernel and 6 more

CVE-2023-4459

Kernel: vmxnet3: null pointer dereference in vmxnet3_rq_cleanup()

A NULL pointer dereference flaw was found in vmxnet3_rq_cleanup in drivers/net/vmxnet3/vmxnet3_drv.c in the networking sub-component in vmxnet3 in the Linux Kernel. This issue may allow a local attacker with normal user privilege to cause a denial of service due to a missing sanity check during cleanup.

CVSS 3.1 · 5.5 Medium EPSS < 1% KEV · Not listed

Vendors

Linux Redhat

Products

Linux Kernel Enterprise Linux Rhel Aus and 5 more

CVE-2023-42754

Kernel: ipv4: null pointer dereference in ipv4_send_dest_unreach()

A NULL pointer dereference flaw was found in the Linux kernel ipv4 stack. The socket buffer (skb) was assumed to be associated with a device before calling __ip_options_compile, which is not always the case if the skb is re-routed by ipvs. This issue may allow a local user with CAP_NET_ADMIN privileges to crash the system.

CVSS 3.1 · 5.5 Medium EPSS < 1% KEV · Not listed

Vendors

Fedoraproject Linux Redhat

Products

Fedora Linux Kernel Enterprise Linux and 1 more

CVE-2023-3106

Kernel: netlink socket crash (null pointer deref) in netlink_dump function

A NULL pointer dereference vulnerability was found in netlink_dump. This issue can occur when the Netlink socket receives the message(sendmsg) for the XFRM_MSG_GETSA, XFRM_MSG_GETPOLICY type message, and the DUMP flag is set and can cause a denial of service or possibly another unspecified impact. Due to the nature of the flaw, privilege escalation cannot be fully ruled out, although it is unlikely.

CVSS 3.1 · 6.6 Medium EPSS < 1% KEV · Not listed

Vendors

Fedoraproject Linux Redhat

Products

Fedora Linux Kernel Enterprise Linux and 1 more

CVE-2026-121402

FreeRDP before 3.32.2 X11 Client Crash via Zero-Width RDPGFX ResetGraphics

FreeRDP before 3.32.2 contains a NULL pointer dereference vulnerability that allows malicious RDP servers to crash xfreerdp clients by sending a zero-width RDPGFX ResetGraphics PDU. The failed resize in gdi_resize_ex leaves the primary display null without ending the session, so a later bitmap update crashes the client in gdi_Bitmap_Paint.

CVSS 4.0 · 7.1 High EPSS < 1% KEV · Not listed

Vendors

Freerdp

Products

Freerdp

CVE-2026-121522

Possible panic from Git source resolver

In 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.

CVSS 4.0 · 6.7 Medium EPSS < 1% KEV · Not listed

Vendors

Moby

Products

Buildkit

CVE-2026-62966

ESPAsyncWebServer multipart parser has null-pointer write

ESPAsyncWebServer is an asynchronous HTTP and WebSocket server library for ESP32, ESP8266, RP2040 and RP2350. Prior to version 3.11.2, the multipart parser in `src/WebRequest.cpp` frees `_itemBuffer` and sets it to NULL when `BOUNDARY_OR_DATA` matches the closing boundary of a file part, before confirming the following terminator, while leaving `_itemIsFile` true. If the next byte is neither the final closing dashes nor a clean CRLF, the `DASH3_OR_RETURN2` or `EXPECT_FEED2` rewind branch re-injects provisionally consumed bytes through `itemWriteByte`. Because `_itemIsFile` remains true, `_itemBuffer`[`_itemBufferIndex`++] writes through a null pointer. On ESP32 this causes a `StoreProhibited` exception, panic and device reboot, producing remote denial of service. A route with a non-trivial body/upload handler, such as a file-upload or web-OTA endpoint, must be present. This issue is fixed in version 3.11.2.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Esp32async

Products

Espasyncwebserver

CVE-2026-59993

Picotls has NULL pointer dereference during handshake, when running as a client

Picotls is a TLS protocol library that allows users select different crypto backends based on their use case. In affected revisions through 44bc503, when picotls is used as a `client-side TLS stack`, a peer can send a `HelloRetryRequest` followed by a `spoofed Hello message` that causes a null-pointer dereference. This can terminate the consuming process, including a process performing other work, resulting in denial of service. This issue is fixed in commit a06ca41.

CVSS 3.1 · 6.5 Medium EPSS < 1% KEV · Not listed

Vendors

—

Products

—

CVE-2026-115403

NULL pointer dereference in the BSD raw IPv6 send path when the destination table is full

In Eclipse ThreadX NetX Duo versions 6.0 through 6.5.2.202603a, built with BSD raw socket and IPv6 support, the IPv6 raw send path uses the destination-table entry it adds without checking that the add succeeded. When the destination table is full and an off-link destination is reached through a default router whose neighbour cache entry is unknown, sending on an IPv6 raw socket with header inclusion dereferences a NULL pointer; a remote sender can fill the table, for example with ICMPv6 Packet Too Big messages, and crash the sending thread.

CVSS 4.0 · 8.2 High EPSS < 1% KEV · Not listed

Vendors

Eclipse

Products

Threadx

CVE-2025-4476

Libsoup: null pointer dereference in libsoup may lead to denial of service

A denial-of-service vulnerability has been identified in the libsoup HTTP client library. This flaw can be triggered when a libsoup client receives a 401 (Unauthorized) HTTP response containing a specifically crafted domain parameter within the WWW-Authenticate header. Processing this malformed header can lead to a crash of the client application using libsoup. An attacker could exploit this by setting up a malicious HTTP server. If a user's application using the vulnerable libsoup library connects to this malicious server, it could result in a denial-of-service. Successful exploitation requires tricking a user's client application into connecting to the attacker's malicious server.

CVSS 3.1 · 4.3 Medium EPSS < 1% KEV · Not listed

Vendors

Redhat

Products

Enterprise Linux Rhel Els