Weakness (CWE)
CWE-476: NULL Pointer Dereference
The product dereferences a pointer that it expects to be valid but is NULL.
How to prevent it (5 mitigations)
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Implementation
For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished [REF-1484].
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Requirements
Select a programming language that is not susceptible to these issues.
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Implementation
Check the results of all functions that return a value and verify that the value is non-null before acting upon it.
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Architecture and Design
Identify all variables and data stores that receive information from external sources, and apply input validation to make sure that they are only initialized to expected values.
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Implementation
Explicitly initialize all variables and other data stores, either during declaration or just before the first usage.
Source: MITRE CWE-476
2,667 results · Feed
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High 7.5
FreeRDP before 3.29.0 Denial of Service via smartcard cache
FreeRDP before 3.29.0 contains a null pointer dereference vulnerability in smartcard cache request decoders that accept NULL NDR pointers for LookupName in SCARD_IOCTL_READCACHEA and SCARD_IOCTL_WRITECACHEA operations. When smartcard emulation is enabled, att…
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High 7.5
FreeRDP before 3.29.0 NULL Dereference via smartcard cleanup
FreeRDP before 3.29.0 contains a null pointer dereference vulnerability in smartcard device control request cleanup when reader-state decoding fails. Attackers can send malformed smartcard IRP requests with non-zero cReaders and truncated reader-state data to…
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High 7.5
NASA Core Flight System (cFS) Health & Safety (HS) Application NULL Pointer Dereference
An incomplete fix for CVE-2026-15352 in the NASA core Flight System (cFS) Health and Safety (HS) application leaves a separate NULL pointer dereference reachable in versions through 7.0.1. An attacker who can trigger the affected command under specific condit…
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High 7.5
Apache Traffic Server: Memory-safety errors in TLS and SNI handling can crash the server
Apache Traffic Server can crash from null dereferences and dangling references in TLS and SNI handling. This issue affects Apache Traffic Server: from 8.0.0 through 8.1.11, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3. Users are recommended to upgrad…
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High 7.5CVE-2026-67184 Public exploit
TinyWeb 0.0.8 Null Pointer Dereference DoS via Malformed HTTP Request
TinyWeb through 0.0.8 contains a null pointer dereference vulnerability that allows unauthenticated remote attackers to crash worker processes by sending a malformed HTTP request line with an invalid version string. The HttpParser::execute() function fails to…
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High 7.5
GitHub MCP Server: Nil Pointer Dereference DoS in completion/complete Handler
GitHub MCP Server is GitHub's official MCP Server. Prior to 1.1.0, the CompletionsHandler function in pkg/github/server.go accesses params.Ref without first checking whether it is nil, so a completion/complete request with a missing or empty ref field trigger…
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Medium 6.5CVE-2026-66749 Public exploit
Let's Chat 0.4.0 - 0.4.8 Denial of Service via Null Dereference in Room Lookup
Let's Chat 0.4.0 through 0.4.8 contains a null dereference vulnerability that allows authenticated attackers to crash the server by supplying a valid 24-character hex string room parameter that matches no document in the database. Attackers can send a crafted…
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High 7.5
net, bpf: check master for NULL in xdp_master_redirect()
In the Linux kernel, the following vulnerability has been resolved: net, bpf: check master for NULL in xdp_master_redirect() xdp_master_redirect() dereferences the result of netdev_master_upper_dev_get_rcu() without a NULL check, but that helper returns NULL …
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Medium 5.2
NULL Pointer Dereference in HDF5 via Invalid Variable-Length Datatype Type Tag
HDF5 contains a NULL pointer dereference vulnerability. Processing a crafted HDF5 file containing an attribute with an invalid variable-length datatype type field may cause the application to crash when the attribute is read.
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Medium 5.3
ggml-org llama.cpp json-schema-to-grammar.cpp _visit_pattern null pointer dereference
A vulnerability was detected in ggml-org llama.cpp d006858/e15efe0. This affects the function _visit_pattern of the file common/json-schema-to-grammar.cpp. The manipulation results in null pointer dereference. The attack can be launched remotely. The pull req…
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High 8.1
x86/ftrace: Relocate %rip-relative percpu refs in dynamic trampolines
In the Linux kernel, the following vulnerability has been resolved: x86/ftrace: Relocate %rip-relative percpu refs in dynamic trampolines With CONFIG_CALL_DEPTH_TRACKING enabled on an x86 retbleed-affected platform (eg: Skylake), with retbleed=stuff, register…
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High 7.5
Apache NimBLE: NULL pointer dereference vulnerability in SMP LTK request
NULL Pointer Dereference vulnerability in Apache NimBLE in LE Long Term Key Request event. This requires disabled asserts (otherwise assert would trigger before NULL dereference) and bogus (or misbehaving) controller, thus severity is low. This issue affects …
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High 7.5
NULL Pointer Dereference in MZ Automation libIEC61850
A NULL pointer dereference in the MMS Write Named Variable List handler, which may allow a network adjacent attacker to crash the server by sending a WriteRequest with an empty listOfData field.
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Medium 6.5
MongoDB $linearFill Window Function Improper Input Validation Leading to Process Termination
A user with read-only privileges is able to craft an aggregation pipeline using the $linearFill window function operator with a specific sortBy expression type to cause the mongod process to terminate abnormally, resulting in denial of service. The issue stem…
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Medium 5.3
Improper Validation of OCSP Response During Outbound TLS Handshake Leading to Process Termination
A MongoDB server initiating an outbound TLS connection may terminate abnormally when processing a malformed OCSP response from a remote peer during the TLS handshake. OCSP stapling validation is enabled by default for outgoing TLS connections. Affected scenar…
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Medium 5.9
'serve-expired-client-timeout' and 'response-ip' CNAME redirect could lead to a crash
In NLnet Labs Unbound 1.10.0 up to and including 1.25.1, when 'serve-expired: yes' is set together with a 'response-ip: <net> redirect' /'response-ip-data: <net> CNAME <target>' rule (or the RPZ 'rpz-cname-override' equivalent), a remote client who controls a…
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Medium 6.9
libheif has a NULL pointer dereference in heif_image_handle_get_image_tiling for malformed unci image missing ispe
libheif is a HEIF and AVIF file format decoder and encoder. Versions prior to 1.22.0 crashes in the public C API `heif_image_handle_get_image_tiling()` when a malformed uncompressed HEIF image item has an associated `uncC` property but no associated `ispe` pr…
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High 8.1
NULL-pointer / out-of-bounds write in Zephyr MCTP I2C+GPIO target binding driven by an unauthenticated I2C controller
The MCTP-over-I2C+GPIO target binding in Zephyr (subsys/pmci/mctp/mctp_i2c_gpio_target.c) processes pseudo-register writes from an I2C bus master byte-by-byte in mctp_i2c_gpio_target_write_received() without validating the order or the receive buffer. In the …
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Medium 5.1
Capstone has a NULL Pointer Dereference with 3DNow! opcodes
Capstone is a disassembly framework. Versions prior to 6.0.0-Alpha8 and 5.0.8 have a NULL pointer dereference in `modRMRequired()` and `decode()` when disassembling 3DNow! opcodes (`0F 0F`) in builds compiled with `-DCAPSTONE_X86_REDUCE`, allowing a remote at…
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Critical 9.8
Invalid pointer in the DOM: Bindings (WebIDL) component
Invalid pointer in the DOM: Bindings (WebIDL) component. This vulnerability was fixed in Firefox 153, Firefox ESR 115.38, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.
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Medium 6.5
NULL Pointer Dereference in REST API properties_parse via Malformed user_properties
In nanomq versions 0.24.11 and earlier, a NULL pointer dereference in `properties_parse()` allows an authenticated attacker to crash the NanoMQ broker by sending a POST request to `/api/v4/mqtt/publish` with `user_properties` as a JSON array instead of a JSON…
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Low 2.6
nanomq NULL Pointer Dereference in MQTTv5 Client CONNECT Decoder Leading to Remote DoS
In nanomq versions 0.24.11 and earlier, a NULL pointer dereference in `nni_mqttv5_msg_decode_connect()` allows a malicious MQTT broker to crash any connecting NanoMQ MQTTv5 client (including bridge mode) with a single packet, causing remote denial of service …
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Medium 6.0
SurrealDB before v2.6.1 Denial of Service via scripting
SurrealDB before v2.6.1 (and before v3.0.0-beta.3) contains a denial of service vulnerability in its embedded JavaScript scripting engine, which is enabled via the --allow-scripting capability (disabled by default). Any user able to execute arbitrary queries …
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High 7.8
ALSA: pcm: Don't setup bogus iov_iter for silencing
In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: Don't setup bogus iov_iter for silencing At transition to the iov_iter for PCM data transfer, we blindly applied the iov_iter setup also for silencing (i.e. data = NULL), and it le…
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High 7.5
net/smc: reject CHID-0 ACCEPT that matches an empty ism_dev slot
In the Linux kernel, the following vulnerability has been resolved: net/smc: reject CHID-0 ACCEPT that matches an empty ism_dev slot On the SMC-D client, slot 0 of ini->ism_dev[]/ini->ism_chid[] is reserved for an SMC-Dv1 device. smc_find_ism_v2_device_clnt()…
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High 7.5
NFSv4/pNFS: reject zero-length r_addr in nfs4_decode_mp_ds_addr
In the Linux kernel, the following vulnerability has been resolved: NFSv4/pNFS: reject zero-length r_addr in nfs4_decode_mp_ds_addr nfs4_decode_mp_ds_addr() decodes the r_netid and r_addr opaques of a netaddr4 from a GETDEVICEINFO multipath-DS body, then imme…
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High 7.5
NASA Core Flight System (cFS) Health & Safety (HS) Application NULL Pointer Dereference
A vulnerability exists in the Health & Safety (HS) application of NASA's Core Flight System (cFS). The flaw allows the application to crash via segmentation fault when processing a routine Housekeeping Telemetry request, leading to denial of service.
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Medium 5.3
CoreDNS: rewrite-plugin EDNS0 response-revert nil-pointer panic (remote DoS) when a downstream plugin returns a response with no OPT record
CoreDNS is a DNS server written in Go. Prior to 1.14.5, the CoreDNS rewrite plugin supports edns0 rewrite rules with an optional revert flag, and two response rules, edns0SetResponseRule and edns0ReplaceResponseRule[T] in plugin/rewrite/edns0.go, call res.IsE…
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High 7.5
CoreDNS: proxyproto plugin panics on PPv2 datagram with non-UDP transport — single 28-byte packet remote DoS
CoreDNS is a DNS server written in Go. Prior to 1.14.4, a single 28-byte UDP datagram can crash the CoreDNS process when the proxyproto plugin is enabled because plugin/pkg/proxyproto/proxyproto.go PacketConn.ReadFrom handles a PROXY v2 header with non-UDP tr…
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Medium 6.5
NGINX Ingress Controller vulnerability
When NGINX Ingress Controller processes Ingress or TransportServer resources, an authenticated, remote attacker with permission to create or modify Ingress or TransportServer resources can cause the NGINX Ingress Controller process to terminate. Impact: The N…
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Medium 6.5
Windows SMB Server Denial of Service Vulnerability
Null pointer dereference in Windows SMB Server allows an authorized attacker to deny service over a network.
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High 7.8
Windows Kernel Elevation of Privilege Vulnerability
Null pointer dereference in Windows Kernel allows an authorized attacker to elevate privileges locally.
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Medium 6.5
Windows Active Directory Domain Services Denial of Service Vulnerability
Null pointer dereference in Active Directory Domain Services allows an authorized attacker to deny service over a network.
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High 7.8
Windows Image Acquisition Elevation of Privilege Vulnerability
Null pointer dereference in Windows Image Acquisition allows an authorized attacker to elevate privileges locally.
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Medium 6.5
Windows Active Directory Domain Services Denial of Service Vulnerability
Null pointer dereference in Active Directory Domain Services allows an authorized attacker to deny service over a network.
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Medium 5.5
User-triggerable kernel NULL-pointer dereference (DoS) in `k_thread_name_copy()` syscall verifier
The CONFIG_USERSPACE verification handler for the k_thread_name_copy() system call (z_vrfy_k_thread_name_copy() in kernel/thread.c) calls k_object_find() on the caller-supplied thread pointer and then dereferences the returned struct k_object without checking…
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Low 3.1
open62541 Shared Client ua_client_connect.c responseReadNamespacesArray null pointer dereference
A vulnerability was identified in open62541 up to 1.5.5. Affected by this issue is the function responseReadNamespacesArray of the file src/client/ua_client_connect.c of the component Shared Client Library. Such manipulation of the argument Server_NamespaceAr…
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Medium 5.7
A null pointer dereference vulnerability exists in the Matter SDK (connectedhomeip) before 1.4.0, affecting the ReadRev…
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High 7.5
Crypt::OpenSSL::X509 versions before 2.1.3 for Perl allow denial of service via NULL pointer dereference
Crypt::OpenSSL::X509 versions before 2.1.3 for Perl allow denial of service via NULL pointer dereference. X509V3_EXT_d2i(ext) returns NULL when an extension's DER value fails to parse. basicC, ia5string, and auth_att dereference its result without a NULL chec…
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Low 3.7
ImageMagick before 7.1.2-26 Heap Use-After-Free via XMP
ImageMagick before 7.1.2-26 contains a heap use-after-free vulnerability caused by missing null check when parsing XMP profiles. Attackers can craft malicious image files with specially crafted XMP data to trigger the vulnerability and cause application crash…