A NULL pointer dereference was found in OpenLDAP server and was fixed in openldap 2.4.55, during a request for renaming RDNs. An unauthenticated attacker could remotely crash the slapd process by sending a specially crafted request, causing a Denial of Service.

In Wireshark 2.4.0 to 2.4.12 and 2.6.0 to 2.6.6, the RPCAP dissector could crash. This was addressed in epan/dissectors/packet-rpcap.c by avoiding an attempted dereference of a NULL conversation.

In Wireshark 2.4.0 to 2.4.12 and 2.6.0 to 2.6.6, the TCAP dissector could crash. This was addressed in epan/dissectors/asn1/tcap/tcap.cnf by avoiding NULL pointer dereferences.

FreeRDP is a free implementation of the Remote Desktop Protocol (RDP), released under the Apache license. Affected versions of FreeRDP are subject to a Null Pointer Dereference leading a crash in the RemoteFX (rfx) handling. Inside the `rfx_process_message_tileset` function, the program allocates tiles using `rfx_allocate_tiles` for the number of numTiles. If the initialization process of tiles is not completed for various reasons, tiles will have a NULL pointer. Which may be accessed in further processing and would cause a program crash. This issue has been addressed in versions 2.11.0 and 3.0.0-beta3. Users are advised to upgrade. There are no known workarounds for this vulnerability.

An exploitable denial-of-service vulnerability exists in the X509 certificate parser of Python.org Python 2.7.11 / 3.6.6. A specially crafted X509 certificate can cause a NULL pointer dereference, resulting in a denial of service. An attacker can initiate or accept TLS connections using crafted certificates to trigger this vulnerability.

flattenSubquery in select.c in SQLite 3.30.1 mishandles certain uses of SELECT DISTINCT involving a LEFT JOIN in which the right-hand side is a view. This can cause a NULL pointer dereference (or incorrect results).

exprListAppendList in window.c in SQLite 3.30.1 allows attackers to trigger an invalid pointer dereference because constant integer values in ORDER BY clauses of window definitions are mishandled.

multiSelect in select.c in SQLite 3.30.1 mishandles certain errors during parsing, as demonstrated by errors from sqlite3WindowRewrite() calls. NOTE: this vulnerability exists because of an incomplete fix for CVE-2019-19880.

An issue was discovered in res_pjsip_t38.c in Sangoma Asterisk through 13.x and Certified Asterisk through 13.21-x. If it receives a re-invite initiating T.38 faxing and has a port of 0 and no c line in the SDP, a NULL pointer dereference and crash will occur. This is different from CVE-2019-18940.

DjVuLibre 3.5.27 has a NULL pointer dereference in the function DJVU::filter_fv at IW44EncodeCodec.cpp.

A flaw was found in the QEMU built-in VNC server. When a client connects to the VNC server, QEMU checks whether the current number of connections crosses a certain threshold and if so, cleans up the previous connection. If the previous connection happens to be in the handshake phase and fails, QEMU cleans up the connection again, resulting in a NULL pointer dereference issue. This could allow a remote unauthenticated client to cause a denial of service.

An issue was discovered in OpenCV before 4.1.1. There is a NULL pointer dereference in the function cv::XMLParser::parse at modules/core/src/persistence.cpp.

A Denial Of Service vulnerability in MiniUPnP MiniUPnPd through 2.1 exists due to a NULL pointer dereference in copyIPv6IfDifferent in pcpserver.c.

ssl/s3_pkt.c in OpenSSL before 0.9.8i allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a DTLS ChangeCipherSpec packet that occurs before ClientHello.

An issue was discovered in GPAC 0.7.1. There is a NULL pointer dereference in the function gf_isom_get_original_format_type at isomedia/drm_sample.c in libgpac.a, as demonstrated by MP4Box.

In Wireshark 2.4.0 to 2.4.13, 2.6.0 to 2.6.7, and 3.0.0, the LDSS dissector could crash. This was addressed in epan/dissectors/packet-ldss.c by handling file digests properly.

An issue was discovered in the Linux kernel before 5.0.7. A NULL pointer dereference can occur when megasas_create_frame_pool() fails in megasas_alloc_cmds() in drivers/scsi/megaraid/megaraid_sas_base.c. This causes a Denial of Service, related to a use-after-free.

cupsd in CUPS 1.3.9 and earlier allows local users, and possibly remote attackers, to cause a denial of service (daemon crash) by adding a large number of RSS Subscriptions, which triggers a NULL pointer dereference. NOTE: this issue can be triggered remotely by leveraging CVE-2008-5184.

In SQLite through 3.22.0, databases whose schema is corrupted using a CREATE TABLE AS statement could cause a NULL pointer dereference, related to build.c and prepare.c.

ncmpc through 0.29 is prone to a NULL pointer dereference flaw. If a user uses the chat screen and another client sends a long chat message, a crash and denial of service could occur.

An issue was discovered in Irssi before 1.0.7 and 1.1.x before 1.1.1. A NULL pointer dereference occurs for an "empty" nick.

An issue was discovered in Irssi before 1.0.7 and 1.1.x before 1.1.1. When the number of windows exceeds the available space, a crash due to a NULL pointer dereference would occur.

In Wireshark 2.4.0 to 2.4.4 and 2.2.0 to 2.2.12, the FCP protocol dissector could crash. This was addressed in epan/dissectors/packet-fcp.c by checking for a NULL pointer.

In Ceph before 12.2.3 and 13.x through 13.0.1, the rgw_civetweb.cc RGWCivetWeb::init_env function in radosgw doesn't handle malformed HTTP headers properly, allowing for denial of service.

LibVNC before commit 4a21bbd097ef7c44bb000c3bd0907f96a10e4ce7 contains null pointer dereference in VNC client code that can result DoS.

ext/imap/php_imap.c in PHP 5.x and 7.x before 7.3.0 allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via an empty string in the message argument to the imap_mail function.

In Wireshark 2.6.0 to 2.6.3 and 2.4.0 to 2.4.9, the MS-WSP protocol dissector could crash. This was addressed in epan/dissectors/packet-mswsp.c by properly handling NULL return values.

A crash can occur when processing a crafted S/MIME message or an XPI package containing a crafted signature. This can be used as a denial-of-service (DOS) attack because Thunderbird reopens the last seen message on restart, triggering the crash again. This vulnerability affects Thunderbird < 60.5.

An issue was discovered in uriparser before 0.9.0. UriCommon.c allows attempted operations on NULL input via a uriResetUri* function.

A flaw was found in the Linux kernel's NFS implementation, all versions 3.x and all versions 4.x up to 4.20. An attacker, who is able to mount an exported NFS filesystem, is able to trigger a null pointer dereference by using an invalid NFS sequence. This can panic the machine and deny access to the NFS server. Any outstanding disk writes to the NFS server will be lost.

gdImageClone in gd.c in libgd 2.1.0-rc2 through 2.2.5 has a NULL pointer dereference allowing attackers to crash an application via a specific function call sequence. Only affects PHP when linked with an external libgd (not bundled).

A flaw was found in the Linux kernel. This flaw allows an attacker to crash the Linux kernel by simulating amateur radio from the user space, resulting in a null-ptr-deref vulnerability and a use-after-free vulnerability.

A NULL pointer dereference vulnerability exists in the xpath.c:xmlXPathCompOpEval() function of libxml2 through 2.9.8 when parsing an invalid XPath expression in the XPATH_OP_AND or XPATH_OP_OR case. Applications processing untrusted XSL format inputs with the use of the libxml2 library may be vulnerable to a denial of service attack due to a crash of the application.

An issue was discovered in mruby 1.4.1. There is a NULL pointer dereference in mrb_class_real because "class BasicObject" is not properly supported in class.c.

In Wireshark 2.6.0, 2.4.0 to 2.4.6, and 2.2.0 to 2.2.14, the DNS dissector could crash. This was addressed in epan/dissectors/packet-dns.c by avoiding a NULL pointer dereference for an empty name in an SRV record.

In Wireshark 2.6.0, 2.4.0 to 2.4.6, and 2.2.0 to 2.2.14, the RRC dissector and other dissectors could crash. This was addressed in epan/proto.c by avoiding a NULL pointer dereference.

An issue was discovered in PHP before 5.6.36, 7.0.x before 7.0.30, 7.1.x before 7.1.17, and 7.2.x before 7.2.5. ext/ldap/ldap.c allows remote LDAP servers to cause a denial of service (NULL pointer dereference and application crash) because of mishandling of the ldap_get_dn return value.

The Squid Software Foundation Squid HTTP Caching Proxy version prior to version 4.0.23 contains a NULL Pointer Dereference vulnerability in HTTP Response X-Forwarded-For header processing that can result in Denial of Service to all clients of the proxy. This attack appear to be exploitable via Remote HTTP server responding with an X-Forwarded-For header to certain types of HTTP request. This vulnerability appears to have been fixed in 4.0.23 and later.

nghttp2 version >= 1.10.0 and nghttp2 <= v1.31.0 contains an Improper Input Validation CWE-20 vulnerability in ALTSVC frame handling that can result in segmentation fault leading to denial of service. This attack appears to be exploitable via network client. This vulnerability appears to have been fixed in >= 1.31.1.

A NULL pointer dereference exists in curl 7.21.0 to and including curl 7.58.0 in the LDAP code that allows an attacker to cause a denial of service

A NULL Pointer Dereference of CWE-476 exists in quassel version 0.12.4 in the quasselcore void CoreAuthHandler::handle(const Login &msg) coreauthhandler.cpp line 235 that allows an attacker to cause a denial of service.

An issue was discovered in Tor before 0.2.9.15, 0.3.1.x before 0.3.1.10, and 0.3.2.x before 0.3.2.10. The directory-authority protocol-list subprotocol implementation allows remote attackers to cause a denial of service (NULL pointer dereference and directory-authority crash) via a misformatted relay descriptor that is mishandled during voting.

In Tor before 0.2.5.16, 0.2.6 through 0.2.8 before 0.2.8.17, 0.2.9 before 0.2.9.14, 0.3.0 before 0.3.0.13, and 0.3.1 before 0.3.1.9, remote attackers can cause a denial of service (NULL pointer dereference and application crash) against directory authorities via a malformed descriptor, aka TROVE-2017-010.

In Irssi before 1.0.3, when receiving a DCC message without source nick/host, it attempts to dereference a NULL pointer. Thus, remote IRC servers can cause a crash.