SB2021072085 - Ubuntu update for linux
Published: July 20, 2021
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 12 secuirty vulnerabilities.
1) Integer overflow (CVE-ID: CVE-2021-33909)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to integer overflow during size_t-to-int conversion when creating, mounting, and deleting a deep directory structure whose total path length exceeds 1GB. An unprivileged local user can write up to 10-byte string to an offset of exactly -2GB-10B below the beginning of a vmalloc()ated kernel buffer.
Successful exploitation of vulnerability may allow an attacker to exploit the our-of-bounds write vulnerability to execute arbitrary code with root privileges.
2) Out-of-bounds write (CVE-ID: CVE-2021-33200)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error in kernel/bpf/verifier.c. A local user can trigger an out-of-bounds write and escalate privileges on the system.
3) Input validation error (CVE-ID: CVE-2020-24586)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists in the 802.11 standard due to the affected device does not clear its cache/memory to remove fragments of an incomplete MSDU/MMPDU from previous session after reconnection/reassociation. A remote attacker on the local network can perform a fragment cache attack and perform a denial of service (DoS) attack.
4) Information disclosure (CVE-ID: CVE-2020-24587)
The vulnerability allows a remote attacker to gain access to potentially sensitive information.
The vulnerability exists due to excessive data output by the application in Windows Wireless Networking. A remote attacker on the local network can gain unauthorized access to sensitive information on the system.
5) Input validation error (CVE-ID: CVE-2020-26139)
The vulnerability allows a remote attacker to compromise the target system.
The vulnerability exists due to forwarding EAPOL frames even though the sender is not yet authenticated. A remote attacker on the local network can cause a denial of service (DoS) condition on the target system.
6) Input validation error (CVE-ID: CVE-2020-26147)
The vulnerability allows a remote attacker to compromise the target system.
The vulnerability exists due to the WEP, WPA, WPA2, and WPA3 implementations reassemble fragments even though some of them were sent in plaintext. A remote attacker on the local network can inject packets and/or exfiltrate selected fragments
7) Security features bypass (CVE-ID: CVE-2020-26558)
The vulnerability allows a remote attacker to compromise the target system.
The vulnerability exists due to an impersonation in the Passkey Entry protocol flaw. A remote attacker on the local network can perform a man-in-the-middle (MITM) attack and impersonate the initiating device without any previous knowledge.
Note: This vulnerability affects the following specifications:
- BR/EDR Secure Simple Pairing in Bluetooth Core Specifications 2.1 through 5.2
- BR/EDR Secure Connections Pairing in Bluetooth Core Specifications 4.1 through 5.2
- LE Secure Connections Pairing in Bluetooth Core Specifications 4.2 through 5.2
8) Improper access control (CVE-ID: CVE-2021-0129)
The vulnerability allows a remote attacker to gain unauthorized access to otherwise restricted functionality.
The vulnerability exists due to improper access restrictions. A remote authenticated attacker on the local network can bypass implemented security restrictions and enable information disclosure
9) Use-after-free (CVE-ID: CVE-2021-23134)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a use-after-free error in nfc sockets in the Linux Kernel. A local user with the CAP_NET_RAW capability can trigger use-after-free and escalate privileges on the system.
10) Information disclosure (CVE-ID: CVE-2021-31829)
The vulnerability allows a local user to gain access to potentially sensitive information.
The vulnerability exists due to excessive data output in the Linux kernel's eBPF verification code. A local user can insert eBPF instructions, use the eBPF verifier to abuse a spectre-like flaw and infer all system memory.
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) Use-after-free (CVE-ID: CVE-2021-33034)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a use-after-free error in net/bluetooth/hci_event.c when destroying an hci_chan. A local user can escalate privileges on the system.
Remediation
Install update from vendor's website.