

Rewterz Threat Alert – Double Dragon APT41, a Dual Espionage and Cyber Crime Operation
August 8, 2019
Rewterz Threat Alert – New Ursnif Variant Spreading Using Word Documents
August 9, 2019
Rewterz Threat Alert – Double Dragon APT41, a Dual Espionage and Cyber Crime Operation
August 8, 2019
Rewterz Threat Alert – New Ursnif Variant Spreading Using Word Documents
August 9, 2019Severity
High
Analysis Summary
CVE 2019-12256
This vulnerability resides in the IPv4 option parsing and may be triggered by IPv4 packets containing invalid options. The most likely outcome of triggering this defect is that the tNet0 task crashes. This vulnerability can result in remote code execution.
CVE 2019-12257
DHCP packets may go past the local area network (LAN) via DHCP-relays, but are otherwise confined to the LAN. The DHCP-client may be used by VxWorks and in the bootrom. Bootrom, using DHCP/BOOTP, is only vulnerable during the boot-process. This vulnerability may be used to overwrite the heap, which could result in a later crash when a task requests memory from the heap. This vulnerability can result in remote code execution.
CVE 2019-12255
An attacker can either hijack an existing TCP-session and inject bad TCP-segments or establish a new TCP-session on any TCP-port listened to by the target. This vulnerability could lead to a buffer overflow of up to a full TCP receive-window (by default, 10k-64k depending on version). The buffer overflow occurs in the task calling recv()/recvfrom()/recvmsg().
Applications that pass a buffer equal to or larger than a full TCP-window are not susceptible to this attack. Applications passing a stack-allocated variable as a buffer are the easiest to exploit.
The most likely outcome is a crash of the application reading from the affected socket, which could result in remote code execution.
CVE 2019-12260
This vulnerability could lead to a buffer overflow of up to a full TCP receive-window (by default, 10k-64k depending on version). The buffer overflow happens in the task calling recv()/recvfrom()/recvmsg().
Applications that pass a buffer equal to or larger than a full TCP-window are not susceptible to this attack. Applications passing a stack-allocated variable as a buffer are the easiest to exploit.
The most likely outcome is a crash of the application reading from the affected socket, which could result in remote code execution.
CVE 2019-12261
The impact of this vulnerability is a buffer overflow of up to a full TCP receive-window (by default, 10k-64k depending on version). The buffer overflow happens in the task calling recv()/recvfrom()/recvmsg().
Applications that pass a buffer equal to or larger than a full TCP-window are not susceptible to this attack. Applications passing a stack-allocated variable as a buffer are the easiest to exploit.
The most likely outcome is a crash of the application reading from the affected socket, which could result in remote code execution.
CVE 2019-12263
This vulnerability relies on a race-condition between the network task (tNet0) and the receiving application. It is very difficult to trigger the race on a system with a single CPU-thread enabled, and there is no way to reliably trigger a race on SMP targets.
CVE 2019-12258
An attacker with the source and destination TCP-port and IP-addresses of a session can inject invalid TCP-segments into the flow, causing the TCP-session to be reset. An application will see this as an ECONNRESET error message when using the socket after such an attack. The most likely outcome is a crash of the application reading from the affected socket.
CVE 2019-12259
An attacker may use CVE 2019-12264 to incorrectly assign a multicast IP-address.
An attacker on the same LAN as the target system may use this vulnerability to cause a NULL-pointer dereference, which most likely will crash the tNet0 task.
CVE 2019-12262
An attacker residing on the LAN can send reverse-ARP responses to the victim system to assign unicast IPv4 addresses to the target.
CVE 2019-12264
An attacker residing on the LAN may choose to hijack a DHCP-client session that requests an IPv4 address. The attacker can send a multicast IP-address in the DHCP offer/ack message, which the victim system then incorrectly assigns. This vulnerability can be combined with CVE-2019-12259 to create a denial-of-service condition.
CVE 2019-12265
The IGMPv3 reception handler does not expect packets to be spread across multiple IP-fragments.
Impact
- Remote code execution
- DoS
Affected Vendors
Wind River
Affected Products
VxWorks
Remediation
Wind River has produced controls and patches to mitigate the reported vulnerabilities.
To obtain patches, email PSIRT@windriver.com and indicate the VxWorks major version for which you need source patches.