CVE-2021-46974
"Linux Kernel BPF Invert Register Vulnerability"
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix masking negation logic upon negative dst register The negation logic for the case where the off_reg is sitting in the dst register is not correct given then we cannot just invert the add to a sub or vice versa. As a fix, perform the final bitwise and-op unconditionally into AX from the off_reg, then move the pointer from the src to dst and finally use AX as the source for the original pointer arithmetic operation such that the inversion yields a correct result. The single non-AX mov in between is possible given constant blinding is retaining it as it's not an immediate based operation.
INFO
Published Date :
Feb. 27, 2024, 7:04 p.m.
Last Modified :
Feb. 28, 2024, 2:06 p.m.
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Remotely Exploitable :
No
Impact Score :
Exploitability Score :
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-46974
.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
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The following list is the news that have been mention
CVE-2021-46974
vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-46974
vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 28, 2024
Action Type Old Value New Value -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 14, 2024
Action Type Old Value New Value -
CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Feb. 27, 2024
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: bpf: Fix masking negation logic upon negative dst register The negation logic for the case where the off_reg is sitting in the dst register is not correct given then we cannot just invert the add to a sub or vice versa. As a fix, perform the final bitwise and-op unconditionally into AX from the off_reg, then move the pointer from the src to dst and finally use AX as the source for the original pointer arithmetic operation such that the inversion yields a correct result. The single non-AX mov in between is possible given constant blinding is retaining it as it's not an immediate based operation. Added Reference Linux https://git.kernel.org/stable/c/4d542ddb88fb2f39bf7f14caa2902f3e8d06f6ba [No types assigned] Added Reference Linux https://git.kernel.org/stable/c/0e2dfdc74a7f4036127356d42ea59388f153f42c [No types assigned] Added Reference Linux https://git.kernel.org/stable/c/53e0db429b37a32b8fc706d0d90eb4583ad13848 [No types assigned] Added Reference Linux https://git.kernel.org/stable/c/2cfa537674cd1051a3b8111536d77d0558f33d5d [No types assigned] Added Reference Linux https://git.kernel.org/stable/c/6eba92a4d4be8feb4dc33976abac544fa99d6ecc [No types assigned] Added Reference Linux https://git.kernel.org/stable/c/7cf64d8679ca1cb20cf57d6a88bfee79a0922a66 [No types assigned] Added Reference Linux https://git.kernel.org/stable/c/b9b34ddbe2076ade359cd5ce7537d5ed019e9807 [No types assigned]
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-46974
is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-46974
weaknesses.