PT-2025-13367 · Linux+4 · Linux Kernel+4

Published 2023-05-09 · Updated 2025-09-29 · CVE-2023-53021

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

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

Name of the Vulnerable Software and Affected Versions Linux kernel versions prior to the fixed version

Description A use-after-free issue has been identified in the Linux kernel, specifically in the sch taprio component. This issue occurs when a taprio qdisc is installed with an invalid TCA RATE attribute, leading to a crash in net tx action(). The problem arises because the hrtimer used by taprio has already fired, causing advance sched() to call netif schedule(), which then attempts to use a destroyed qdisc. The estimated number of potentially affected devices is not provided.

Recommendations For Linux kernel versions prior to the fixed version, consider disabling the sch taprio component until a patch is available. As a temporary workaround, restrict access to the vulnerable qdisc to minimize the risk of exploitation. Avoid using the TCA RATE attribute in the affected API endpoint until the issue is resolved. At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

DoS

Use After Free

Weakness Enumeration

CWE-416

Related Identifiers

ALSA-2025_16880

BDU:2025-06346

CESA-2023_7077

CVE-2023-53021

RHSA-2023:2458

RHSA-2023:7077

RHSA-2023_2458

RHSA-2023_7077

Affected Products

Astra Linux

Centos

Linux Kernel

Red Hat

Red Os

References · 25

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53021.json · Exploit
• https://git.kernel.org/stable/c/3a415d59c1dbec9d772dbfab2d2520d98360caae · Patch
• https://cve.org/CVERecord?id=CVE-2023-53021 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2023-53021 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2023-53021 · Vendor Advisory
• https://bdu.fstec.ru/vul/2025-06346 · Security Note
• https://osv.dev/vulnerability/DEBIAN-CVE-2023-53021 · Vendor Advisory
• https://git.kernel.org/stable/c/c60fe70078d6e515f424cb868d07e00411b27fbc · Patch
• https://git.kernel.org/stable/c/1200388a0b1c3c6fda48d4d2143db8f7e4ef5348 · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2023-53021 · Vendor Advisory
• https://ubuntu.com/security/CVE-2023-53021 · Vendor Advisory
• https://git.kernel.org/stable/c/d3b2d2820a005e43855fa71b80c4a4b194201c60 · Patch
• https://git.kernel.org/stable/c/c53acbf2facfdfabdc6e6984a1a38f5d38b606a1 · Patch
• https://osv.dev/vulnerability/BELL-CVE-2023-53021 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2023-53021 · Security Note