CVE-2021-3490

Severity CVSS v4.0:
Pending analysis
Type:
CWE-125 Out-of-bounds Read
Publication date:
04/06/2021
Last modified:
14/09/2021

Description

The eBPF ALU32 bounds tracking for bitwise ops (AND, OR and XOR) in the Linux kernel did not properly update 32-bit bounds, which could be turned into out of bounds reads and writes in the Linux kernel and therefore, arbitrary code execution. This issue was fixed via commit 049c4e13714e ("bpf: Fix alu32 const subreg bound tracking on bitwise operations") (v5.13-rc4) and backported to the stable kernels in v5.12.4, v5.11.21, and v5.10.37. The AND/OR issues were introduced by commit 3f50f132d840 ("bpf: Verifier, do explicit ALU32 bounds tracking") (5.7-rc1) and the XOR variant was introduced by 2921c90d4718 ("bpf:Fix a verifier failure with xor") ( 5.10-rc1).

Vulnerable products and versions

CPE From Up to
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 5.10 (including) 5.10.37 (excluding)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 5.11 (including) 5.11.21 (excluding)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 5.12 (including) 5.12.4 (excluding)
cpe:2.3:o:linux:linux_kernel:5.13:-:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:20.10:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:21.04:*:*:*:*:*:*:*