CVE-2021-31956
Windows NTFS Elevation of Privilege Vulnerability
ACTIVELY EXPLOITED IN THE WILD
This vulnerability is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
Microsoft Windows NTFS Privilege Escalation Vulnerability
Microsoft Windows
Apply updates per vendor instructions.
11/3/2021
https://nvd.nist.gov/vuln/detail/CVE-2021-31956
Vulnerability Summary
CVSS v3 Score
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS v2 Score
AV:N/AC:M/Au:N/C:C/I:C/A:C
EPSS Score (Exploitation Probability)
This vulnerability has a 88.71% probability of being exploited in the next 30 days, ranking higher than 100% of all scored CVEs.
CWE Classification
Related Vulnerabilities
Same Weakness Type(CWE-191)
CryptoLib provides a software-only solution using the CCSDS Space Data Link Security Protocol - Extended Procedures (SDLS-EP) to secure communications between a spacecraft running the core Flight System (cFS) and a ground station. A critical heap buffer overflow vulnerability was identified in the `Crypto_TC_Prep_AAD` function of CryptoLib versions 1.3.3 and prior. This vulnerability allows an attacker to trigger a Denial of Service (DoS) or potentially execute arbitrary code (RCE) by providing a maliciously crafted telecommand (TC) frame that causes an unsigned integer underflow. The vulnerability lies in the function `Crypto_TC_Prep_AAD`, specifically during the computation of `tc_mac_start_index`. The affected code incorrectly calculates the MAC start index without ensuring it remains within the bounds of the `ingest` buffer. When `tc_mac_start_index` underflows due to an incorrect length calculation, the function attempts to access an out-of-bounds memory location, leading to a segmentation fault. The vulnerability is still present in the repository as of commit `d3cc420ace96d02a5b7e83d88cbd2e48010d5723`.
CryptoLib provides a software-only solution using the CCSDS Space Data Link Security Protocol - Extended Procedures (SDLS-EP) to secure communications between a spacecraft running the core Flight System (cFS) and a ground station. In versions 1.3.3 and prior, an unsigned integer underflow in the `Crypto_TC_ProcessSecurity` function of CryptoLib leads to a heap buffer overflow. The vulnerability is triggered when the `fl` (frame length) field in a Telecommand (TC) packet is set to 0. This underflow causes the frame length to be interpreted as 65535, resulting in out-of-bounds memory access. This critical vulnerability can be exploited to cause a denial of service (DoS) or potentially achieve remote code execution. Users of CryptoLib are advised to apply the recommended patch or avoid processing untrusted TC packets until a fix is available.
An integer underflow during deserialization may allow any unauthenticated user to read out of bounds heap memory. This may result into secret data or pointers revealing the layout of the address space to be included into a deserialized data structure, which may potentially lead to thread crashes or cause denial of service conditions.
In store_upgrade and store_cmd of drivers/input/touchscreen/stm/ftm4_pdc.c, there are out of bound writes due to missing bounds checks or integer underflows. These could lead to escalation of privilege.
Windows TCP/IP Remote Code Execution Vulnerability
Similar SeverityHIGH
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