CVE-2021-47089

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

kfence: fix memory leak when cat kfence objects

Hulk robot reported a kmemleak problem:

unreferenced object 0xffff93d1d8cc02e8 (size 248):

comm "cat", pid 23327, jiffies 4624670141 (age 495992.217s)

hex dump (first 32 bytes):

00 40 85 19 d4 93 ff ff 00 10 00 00 00 00 00 00 .@..............

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

backtrace:

seq_open+0x2a/0x80

full_proxy_open+0x167/0x1e0

do_dentry_open+0x1e1/0x3a0

path_openat+0x961/0xa20

do_filp_open+0xae/0x120

do_sys_openat2+0x216/0x2f0

do_sys_open+0x57/0x80

do_syscall_64+0x33/0x40

entry_SYSCALL_64_after_hwframe+0x44/0xa9

unreferenced object 0xffff93d419854000 (size 4096):

comm "cat", pid 23327, jiffies 4624670141 (age 495992.217s)

hex dump (first 32 bytes):

6b 66 65 6e 63 65 2d 23 32 35 30 3a 20 30

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References