#VU87989 Out-of-bounds write in Linux kernel - CVE-2021-33200

Vulnerability identifier: #VU87989

Vulnerability risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-33200

CWE-ID: CWE-787

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description

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.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: All versions

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External links
https://www.openwall.com/lists/oss-security/2021/05/27/1
https://security.netapp.com/advisory/ntap-20210706-0004/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JJCABL43FT3FKRX5DBPZG25FNKR6CEK4/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7LR3OKKPHIBGOMHN476CMLW2T7UG53QX/
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=3d0220f6861d713213b015b582e9f21e5b28d2e0
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=bb01a1bba579b4b1c5566af24d95f1767859771e
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=a7036191277f9fa68d92f2071ddc38c09b1e5ee5

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.