SB2021092811 - Multiple vulnerabilities in Red Hat Advanced Cluster Management for Kubernetes
Published: September 28, 2021 Updated: February 8, 2024
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 13 secuirty vulnerabilities.
1) Off-by-one (CVE-ID: CVE-2021-23017)
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to an off-by-one error within the ngx_resolver_copy() function when processing DNS responses. A remote attacker can trigger an off-by-one error, write a dot character (‘.’, 0x2E) out of bounds in a heap allocated buffer and execute arbitrary code on the system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
The vulnerability can be triggered by a DNS response in reply to a DNS request from nginx when the resolver primitive is configured. A specially crafted packet allows overwriting the least significant byte of next heap chunk metadata with 0x2E.
2) Missing Authorization (CVE-ID: CVE-2020-27777)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to the way RTAS handles memory accesses in userspace to kernel communication. On a locked down (usually due to Secure Boot) guest system running on top of PowerVM or KVM hypervisors (pseries platform) a root like user could use this flaw to further increase their privileges to that of a running kernel.
3) Security restrictions bypass (CVE-ID: CVE-2021-3653)
The vulnerability allows a malicious guest to escalate privileges on the system.
The vulnerability exists due to improperly imposed security restrictions within the KVM's AMD code for supporting SVM nested virtualization. The flaw occurs when processing the VMCB (virtual machine control block) provided by the L1 guest to spawn/handle a nested guest (L2). Due to improper validation of the "int_ctl" field, this issue could allow a malicious L1 to enable AVIC support (Advanced Virtual Interrupt Controller) for the L2 guest.
As a result, the L2 guest would be allowed to read/write physical pages of the host, resulting in a crash of the entire system, leak of sensitive data or potential guest-to-host escape.
4) Out-of-bounds write (CVE-ID: CVE-2021-22555)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error when processing untrusted input in net/netfilter/x_tables.c in Linux kernel. A local user can run a specially crafted program to trigger an out-of-bounds write and execute arbitrary code with elevated privileges.
5) XML External Entity injection (CVE-ID: CVE-2021-22922)
The vulnerability allows a remote attacker to gain access to sensitive information.
The vulnerability exists due to insufficient validation of user-supplied XML input. A remote attacker can pass a specially crafted XML code to the affected application and view contents of arbitrary files on the system or initiate requests to external systems.
Successful exploitation of the vulnerability may allow an attacker to view contents of arbitrary file on the server or perform network scanning of internal and external infrastructure.
6) Insufficiently protected credentials (CVE-ID: CVE-2021-22923)
The vulnerability allows a remote attacker to compromise the target system.
The vulnerability exists due to insufficiently protected credentials. A remote attacker can gain access to sensitive information on the target system.
7) Improper Certificate Validation (CVE-ID: CVE-2021-22924)
The vulnerability allows a remote attacker to compromise the target system.
The vulnerability exists due to errors in the logic when the config matching function does not take "issuer cert" into account and it compares the involved paths case insensitively. A remote attacker can gain access to sensitive information on the system.
8) Command Injection (CVE-ID: CVE-2021-29154)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to incorrect computation of branch displacements within the BPF JIT compilers in the Linux kernel in arch/x86/net/bpf_jit_comp.c and arch/x86/net/bpf_jit_comp32.c. A local user can inject and execute arbitrary commands with elevated privileges.
9) Buffer overflow (CVE-ID: CVE-2021-29650)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to a boundary error within the netfilter subsystem in net/netfilter/x_tables.c and include/linux/netfilter/x_tables.h. A local user can trigger memory corruption upon the assignment of a new table value and cause denial of service.
10) Input validation error (CVE-ID: CVE-2021-31535)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to insufficient validation of color names within the XLookupColor() function. A local user can run a specially crafted application on the system and perform a denial of service (DoS) attack.
11) Race condition (CVE-ID: CVE-2021-32399)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a race condition for removal of the HCI controller within net/bluetooth/hci_request.c in the Linux kernel. A local user can exploit the race and gain unauthorized access to sensitive information and escalate privileges on the system.
12) NULL pointer dereference (CVE-ID: CVE-2021-36222)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a NULL pointer dereference error in kdc/kdc_preauth_ec.c in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5). A remote attacker can send a request containing a PA-ENCRYPTED-CHALLENGE padata element without using FAST and perform a denial of service (DoS) attack.
13) NULL pointer dereference (CVE-ID: CVE-2021-37750)
The vulnerability allows a remote user to perform a denial of service (DoS) attack.
The vulnerability exists due to a NULL pointer dereference error in the Key Distribution Center (KDC) in kdc/do_tgs_req.c. A remote user can pass specially crafted data via the FAST inner body that lacks a server field, trigger a NULL pointer dereference error and perform a denial of service (DoS) attack.
Remediation
Install update from vendor's website.