medium 5.5

CVE-2021-47171 json

net: usb: fix memory leak in smsc75xx_bind

published 2024-03-25 2 y ago modified 2026-06-17 4 mo ago also EUVD-2021-33819

cvss: 5.5; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 15%
public exploits: 0; none known

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

Syzbot reported memory leak in smsc75xx_bind(). The problem was is non-freed memory in case of errors after memory allocation.

backtrace: [<ffffffff84245b62>] kmalloc include/linux/slab.h:556 [inline] [<ffffffff84245b62>] kzalloc include/linux/slab.h:686 [inline] [<ffffffff84245b62>] smsc75xx_bind+0x7a/0x334 drivers/net/usb/smsc75xx.c:1460 [<ffffffff82b5b2e6>] usbnet_probe+0x3b6/0xc30 drivers/net/usb/usbnet.c:1728

Patch / fix

fixed in 1 distros 6 links 8

Linux Linux 4.4.271, 4.9.271, 4.14.235, 4.19.193, 5.4.124, 5.10.42, 5.12.9, 5.13

debian ubuntu red hat suse almalinux rocky linux

linux Debian 14, Debian 13, Debian 12 5.14.6-1

debian advisories DEBIAN-CVE-2021-47171

linux Ubuntu 18.04 LTS 4.15.0-151.157
linux Ubuntu 20.04 LTS 5.4.0-80.90
linux-aws Ubuntu 18.04 LTS 4.15.0-1109.116
linux-aws Ubuntu 20.04 LTS 5.4.0-1054.57
linux-gcp Ubuntu 20.04 LTS 5.4.0-1049.53
linux-kvm Ubuntu 18.04 LTS 4.15.0-1097.99
linux-kvm Ubuntu 20.04 LTS 5.4.0-1044.46
linux-azure Ubuntu 20.04 LTS 5.4.0-1055.57

ubuntu advisories UBUNTU-CVE-2021-47171

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

kernel-rt RHEL 8 4.18.0-553.5.1.rt7.346.el8_10
kernel-rt-kvm RHEL 8 4.18.0-553.5.1.rt7.346.el8_10
kernel-rt-core RHEL 8 4.18.0-553.5.1.rt7.346.el8_10
kernel-rt-modules RHEL 8 4.18.0-553.5.1.rt7.346.el8_10
kernel-rt-debug-kvm RHEL 8 4.18.0-553.5.1.rt7.346.el8_10
kernel-rt-debug-core RHEL 8 4.18.0-553.5.1.rt7.346.el8_10
kernel-rt-debug-modules RHEL 8 4.18.0-553.5.1.rt7.346.el8_10
kernel-rt-modules-extra RHEL 8 4.18.0-553.5.1.rt7.346.el8_10

red hat advisories RHSA-2024:3627 RHSA-2024:3618

kernel-syms SLES for SAP 12 SP5, SLES 12 SP5 4.12.14-122.219.1
kernel-source SLES for SAP 12 SP5, SLES 12 SP5 4.12.14-122.219.1
kernel-default SLES for SAP 12 SP5, SLES 12 SP5, SLE Workstation Extension 12 SP5 +2 more 4.12.14-122.219.1
kernel-obs-build SLE Software Development Kit 12 SP5 4.12.14-122.219.1
kernel-rt SLE Real Time 12 SP5 4.12.14-10.188.1
kernel-syms-rt SLE Real Time 12 SP5 4.12.14-10.188.1
kernel-rt_debug SLE Real Time 12 SP5 4.12.14-10.188.1
kernel-source-rt SLE Real Time 12 SP5 4.12.14-10.188.1

suse advisories SUSE-SU-2024:2184-1 SUSE-SU-2024:1983-1 SUSE-SU-2024:1979-1 SUSE-SU-2024:1870-1 SUSE-SU-2024:1646-1 SUSE-SU-2024:1643-1

kernel AlmaLinux 8 4.18.0-553.5.1.el8_10
perf AlmaLinux 8 4.18.0-553.5.1.el8_10
bpftool AlmaLinux 8 4.18.0-553.5.1.el8_10
kernel-core AlmaLinux 8 4.18.0-553.5.1.el8_10
kernel-tools AlmaLinux 8 4.18.0-553.5.1.el8_10
python3-perf AlmaLinux 8 4.18.0-553.5.1.el8_10
kernel-modules AlmaLinux 8 4.18.0-553.5.1.el8_10
kernel-zfcpdump AlmaLinux 8 4.18.0-553.5.1.el8_10

almalinux advisories ALSA-2024:3618 ALSA-2024:3627

kernel-rt Rocky Linux 8 4.18.0-553.5.1.rt7.346.el8_10
kernel Rocky Linux 8 4.18.0-553.5.1.el8_10

rocky linux advisories RLSA-2024:3627 RLSA-2024:3618

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2021-47171 updated 2026-11-06 cvss 4.4

kernel: net: usb: fix memory leak in smsc75xx_bind

Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more
affected: no fix planned “Out of support scope”
Red Hat Enterprise Linux BaseOS (v. 8) perf 4.18.0-553.5.1.el8_10, kernel 4.18.0-553.5.1.el8_10, bpftool 4.18.0-553.5.1.el8_10, kernel-core 4.18.0-553.5.1.el8_10, kernel-tools 4.18.0-553.5.1.el8_10, python3-perf 4.18.0-553.5.1.el8_10, +15 more Red Hat Enterprise Linux CRB (v. 8) kernel-debuginfo-common-x86_64 4.18.0-553.5.1.el8_10, kernel-debuginfo-common-aarch64 4.18.0-553.5.1.el8_10, kernel-debuginfo-common-ppc64le 4.18.0-553.5.1.el8_10
fixed: vendor fix RHSA-2024:3618
Red Hat Enterprise Linux NFV (v. 8) kernel-rt 4.18.0-553.5.1.rt7.346.el8_10, kernel-rt-kvm 4.18.0-553.5.1.rt7.346.el8_10, kernel-rt-core 4.18.0-553.5.1.rt7.346.el8_10, kernel-rt-modules 4.18.0-553.5.1.rt7.346.el8_10, kernel-rt-debug-kvm 4.18.0-553.5.1.rt7.346.el8_10, kernel-rt-debug-core 4.18.0-553.5.1.rt7.346.el8_10, +4 more Red Hat Enterprise Linux RT (v. 8) kernel-rt 4.18.0-553.5.1.rt7.346.el8_10, kernel-rt-core 4.18.0-553.5.1.rt7.346.el8_10, kernel-rt-modules 4.18.0-553.5.1.rt7.346.el8_10, kernel-rt-debug-core 4.18.0-553.5.1.rt7.346.el8_10, kernel-rt-debug-modules 4.18.0-553.5.1.rt7.346.el8_10, kernel-rt-modules-extra 4.18.0-553.5.1.rt7.346.el8_10, +2 more
fixed: vendor fix RHSA-2024:3627
Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 2 y ago (2024-09-10)

Exploit prediction

0.24% chance of exploitation in the next 30 days, higher than 15% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.1	5.5	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products

Linux Linux

Classification

Weakness

CWE-401 Missing Release of Memory after Effective Lifetime

Technology feeds

Linux kernel rss critical rss

References

Sources

CVE List CVE-2021-47171
NVD CVE-2021-47171

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary