CVE-2023-3776

2023-07-2100:00:00

ubuntu.com

7.8 High

CVSS3

Attack Vector

LOCAL

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

HIGH

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

4.3 Medium

CVSS2

Access Vector

LOCAL

Access Complexity

LOW

Authentication

SINGLE

Confidentiality Impact

PARTIAL

Integrity Impact

PARTIAL

Availability Impact

PARTIAL

AV:L/AC:L/Au:S/C:P/I:P/A:P

0.0004 Low

EPSS

Percentile

5.2%

JSON

A use-after-free vulnerability in the Linux kernel’s net/sched: cls_fw
component can be exploited to achieve local privilege escalation. If
tcf_change_indev() fails, fw_set_parms() will immediately return an error
after incrementing or decrementing the reference counter in
tcf_bind_filter(). If an attacker can control the reference counter and set
it to zero, they can cause the reference to be freed, leading to a
use-after-free vulnerability. We recommend upgrading past commit
0323bce598eea038714f941ce2b22541c46d488f.

Bugs

Notes

Author	Note
	Priority reason: By using unprivileged user namespaces, this can be exploited to achieve local privilege escalation.

OSVersionArchitecturePackageVersionFilename
ubuntu18.04noarchlinux< 4.15.0-216.227) Available with Ubuntu Pro or Ubuntu Pro (Infra-onlyUNKNOWN
ubuntu20.04noarchlinux< 5.4.0-159.176UNKNOWN
ubuntu22.04noarchlinux< 5.15.0-82.91UNKNOWN
ubuntu23.04noarchlinux< 6.2.0-31.31UNKNOWN
ubuntu24.04noarchlinux< anyUNKNOWN
ubuntu14.04noarchlinux< 3.13.0-193.244) Available with Ubuntu Pro or Ubuntu Pro (Infra-onlyUNKNOWN
ubuntu16.04noarchlinux< 4.4.0-244.278) Available with Ubuntu Pro or Ubuntu Pro (Infra-onlyUNKNOWN
ubuntu18.04noarchlinux-aws< 4.15.0-1160.173) Available with Ubuntu Pro or Ubuntu Pro (Infra-onlyUNKNOWN
ubuntu20.04noarchlinux-aws< 5.4.0-1108.116UNKNOWN
ubuntu22.04noarchlinux-aws< 5.15.0-1043.48UNKNOWN

OS	Version	Architecture	Package	Version	Filename
ubuntu	18.04	noarch	linux	< 4.15.0-216.227) Available with Ubuntu Pro or Ubuntu Pro (Infra-only	UNKNOWN
ubuntu	20.04	noarch	linux	< 5.4.0-159.176	UNKNOWN
ubuntu	22.04	noarch	linux	< 5.15.0-82.91	UNKNOWN
ubuntu	23.04	noarch	linux	< 6.2.0-31.31	UNKNOWN
ubuntu	24.04	noarch	linux	< any	UNKNOWN
ubuntu	14.04	noarch	linux	< 3.13.0-193.244) Available with Ubuntu Pro or Ubuntu Pro (Infra-only	UNKNOWN
ubuntu	16.04	noarch	linux	< 4.4.0-244.278) Available with Ubuntu Pro or Ubuntu Pro (Infra-only	UNKNOWN
ubuntu	18.04	noarch	linux-aws	< 4.15.0-1160.173) Available with Ubuntu Pro or Ubuntu Pro (Infra-only	UNKNOWN
ubuntu	20.04	noarch	linux-aws	< 5.4.0-1108.116	UNKNOWN
ubuntu	22.04	noarch	linux-aws	< 5.15.0-1043.48	UNKNOWN