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CVE-2021-33200

HIGHCVSS 7.8/10EPSS 0.38%

Last modified

CVE-2021-33200 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. kernel/bpf/verifier.c in the Linux kernel through 5.12.7 enforces incorrect limits for pointer arithmetic operations, aka CID-bb01a1bba579. This can be abused to perform out-of-bounds reads and writes in kernel memory, leading to local privilege escalation to root. EPSS estimates a 0.38% chance of exploitation in the next 30 days.

Description

kernel/bpf/verifier.c in the Linux kernel through 5.12.7 enforces incorrect limits for pointer arithmetic operations, aka CID-bb01a1bba579. This can be abused to perform out-of-bounds reads and writes in kernel memory, leading to local privilege escalation to root. In particular, there is a corner case where the off reg causes a masking direction change, which then results in an incorrect final aux->alu_limit.

Metrics

CVSS 3.1
7.8/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability
0.38%

29.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersions
LinuxLinux Kernel>= 5.4.116, < 5.4.123
LinuxLinux Kernel>= 5.10.33, < 5.10.41
LinuxLinux Kernel>= 5.11.17, < 5.12.8
FedoraprojectFedora33
FedoraprojectFedora34
NetappCloud BackupAll versions
NetappSolidfire \& Hci Management NodeAll versions
NetappSolidfire Baseboard Management ControllerAll versions
NetappH300s FirmwareAll versions
NetappH500s FirmwareAll versions
NetappH300e FirmwareAll versions
NetappH500e FirmwareAll versions
NetappH700e FirmwareAll versions
NetappH410s FirmwareAll versions
NetappH700s FirmwareAll versions

References

Timeline

Published
Last Modified
Status
Modified

Frequently Asked Questions

What is CVE-2021-33200?
kernel/bpf/verifier.c in the Linux kernel through 5.12.7 enforces incorrect limits for pointer arithmetic operations, aka CID-bb01a1bba579. This can be abused to perform out-of-bounds reads and writes in kernel memory, leading to local privilege escalation to root. In particular, there is a corner case where the off reg causes a masking direction change, which then results in an incorrect final aux->alu_limit.
How severe is CVE-2021-33200?
CVE-2021-33200 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 0.38% probability of exploitation in the next 30 days.
How do I fix CVE-2021-33200?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-33200?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST