HTTP/2: Multiple HTTP/2 enabled web servers are vulnerable to a DDoS attack (Rapid Reset Attack)

The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023.

A vulnerability in the web-based management interface of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) could allow an authenticated, remote attacker with read-write privileges on the application to perform a command injection attack that could result in remote code execution on an affected device. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending a crafted request to the web-based management interface of an affected device. A successful exploit could allow the attacker to establish a remote shell with root privileges.

A vulnerability in the web-based management interface of Cisco Expressway Series could allow an unauthenticated, remote attacker to redirect a user to a malicious web page. This vulnerability is due to improper input validation of HTTP request parameters. An attacker could exploit this vulnerability by intercepting and modifying an HTTP request from a user. A successful exploit could allow the attacker to redirect the user to a malicious web page. Note: Cisco Expressway Series refers to Cisco Expressway Control (Expressway-C) devices and Cisco Expressway Edge (Expressway-E) devices.

Cisco Expressway Series and Cisco TelePresence VCS Improper Certificate Validation Vulnerability

A vulnerability in the certificate validation of Cisco Expressway-C and Cisco TelePresence VCS could allow an unauthenticated, remote attacker to gain unauthorized access to sensitive data.  The vulnerability is due to a lack of validation of the SSL server certificate that an affected device receives when it establishes a connection to a Cisco Unified Communications Manager device. An attacker could exploit this vulnerability by using a man-in-the-middle technique to intercept the traffic between the devices, and then using a self-signed certificate to impersonate the endpoint. A successful exploit could allow the attacker to view the intercepted traffic in clear text or alter the contents of the traffic. Note: Cisco Expressway-E is not affected by this vulnerability.Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

Cisco Expressway Series and Cisco TelePresence VCS Cross-Site Request Forgery Vulnerability

A vulnerability in the REST API of Cisco Expressway Series and Cisco TelePresence VCS could allow an unauthenticated, remote attacker to conduct a cross-site request forgery (CSRF) attack on an affected system. This vulnerability is due to insufficient CSRF protections for the web-based management interface of an affected system. An attacker could exploit this vulnerability by persuading a user of the REST API to follow a crafted link. A successful exploit could allow the attacker to cause the affected system to reload. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. 

A vulnerability in the cluster database (CDB) management component of Cisco Expressway Series Software and Cisco TelePresence Video Communication Server (VCS) Software could allow an authenticated, remote attacker to cause the CDB process on an affected system to restart unexpectedly, resulting in a temporary denial of service (DoS) condition. The vulnerability is due to incomplete input validation of URL requests by the REST API of the affected software. An attacker could exploit this vulnerability by sending a crafted URL to the REST API of the affected software on an affected system. A successful exploit could allow the attacker to cause the CDB process on the affected system to restart unexpectedly, resulting in a temporary DoS condition. Cisco Bug IDs: CSCve77571.

A vulnerability in the Session Initiation Protocol (SIP) on the Cisco TelePresence Video Communication Server (VCS) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the targeted appliance. The vulnerability is due to excessive SIP traffic sent to the device. An attacker could exploit this vulnerability by transmitting large volumes of SIP traffic to the VCS. An exploit could allow the attacker to cause a complete DoS condition on the targeted system. Cisco Bug IDs: CSCve32897.

A vulnerability in the received packet parser of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) software could allow an unauthenticated, remote attacker to cause a reload of the affected system, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient size validation of user-supplied data. An attacker could exploit this vulnerability by sending crafted H.224 data in Real-Time Transport Protocol (RTP) packets in an H.323 call. An exploit could allow the attacker to overflow a buffer in a cache that belongs to the received packet parser, which will result in a crash of the application, resulting in a DoS condition. All versions of Cisco Expressway Series Software and Cisco TelePresence VCS Software prior to version X8.8.2 are vulnerable. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. Cisco Bug IDs: CSCus99263.

The CLI in Cisco TelePresence Video Communication Server (VCS) Expressway X8.5.2 allows local users to obtain root privileges by writing script arguments to an unspecified file, aka Bug ID CSCuv12542.

The Session Description Protocol (SDP) implementation in Cisco TelePresence Video Communication Server (VCS) and Cisco Expressway before X8.2 and Cisco TelePresence Conductor before XC2.4 allows remote attackers to cause a denial of service (mishandled exception and device reload) via a crafted media description, aka Bug IDs CSCus96593 and CSCun73192.

The process-management implementation in Cisco TelePresence Video Communication Server (VCS) Expressway X8.5.2 allows local users to gain privileges by terminating a firestarter.py supervised process and then triggering the restart of a process by the root account, aka Bug ID CSCuv12272.

The management interface in Cisco TelePresence Video Communication Server (VCS) and Cisco Expressway before X7.2.4, X8 before X8.1.2, and X8.2 before X8.2.2 and Cisco TelePresence Conductor before X2.3.1 and XC2.4 before XC2.4.1 allows remote attackers to bypass authentication via crafted login parameters, aka Bug IDs CSCur02680 and CSCur05556.

Cross-site scripting (XSS) vulnerability in Cisco TelePresence Video Communication Server (VCS) X8.5.1 allows remote attackers to inject arbitrary web script or HTML via a crafted URL, aka Bug ID CSCut27635.

Cisco TelePresence Video Communication Server (VCS) X8.5RC4 allows remote attackers to cause a denial of service (CPU consumption or device outage) via a crafted SDP parameter-negotiation request in an SDP session during a SIP connection, aka Bug ID CSCut42422.

Cisco TelePresence Video Communication Server (VCS) Expressway X8.5.2 improperly checks for a user account's read-only attribute, which allows remote authenticated users to execute arbitrary OS commands via crafted HTTP requests, as demonstrated by read or write operations on the Unified Communications lookup page, aka Bug ID CSCuv12552.

Cisco TelePresence Video Communication Server (VCS) and Cisco Expressway allow remote attackers to cause a denial of service (memory and CPU consumption, and partial outage) via crafted SIP packets, aka Bug ID CSCur12473.

Cisco TelePresence Video Communication Server (VCS) Expressway X8.5.2 allows remote attackers to cause a denial of service via invalid variables in an authentication packet, aka Bug ID CSCuv40469.

Cisco TelePresence Video Communication Server (VCS) and Expressway Software before X8.1.1 allow remote attackers to cause a denial of service (device reload) via crafted SIP packets, aka Bug IDs CSCum60442 and CSCum60447.

The password-change feature in the administrative web interface in Cisco TelePresence Video Communication Server (VCS) Expressway X8.5.1 improperly performs authorization, which allows remote authenticated users to reset arbitrary active-user passwords via unspecified vectors, aka Bug ID CSCuv12338.

The Mobile and Remote Access (MRA) endpoint-validation feature in Cisco TelePresence Video Communication Server (VCS) Expressway X8.5.2 improperly validates the phone line used for registration, which allows remote authenticated users to conduct impersonation attacks via a crafted registration, aka Bug ID CSCuv40396.