CVE-2023-53624: linux kernel Integer Overflow — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_fq: fix integer overflow of "credit" if sch_fq is configured with "initial quantum" having values greater than INT_MAX, the first assignment of "credit" does signed integer overflow to a very negative value. In this situation, the syzkaller script provided by Cristoph triggers the CPU soft-lockup warning even with few sockets. It's not an infinite loop, but "credit" wasn't probably meant to be minus 2Gb for each new flow. Capping "initial quantum" to INT_MAX proved to fix the issue. v2: validation of "initial quantum" is done in fq_policy, instead of open coding in fq_change() _ suggested by Jakub Kicinski

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CVSS v3.1 Score

5.5

MEDIUM

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

Weakness Type (CWE)

CWE-190 Integer Overflow

Affected Products

Vendor	Product	Versions
linux	linux_kernel	3.12 — 5.10.180
linux	linux_kernel	5.11 — 5.15.111
linux	linux_kernel	5.16 — 6.1.28
linux	linux_kernel	6.2 — 6.2.15
linux	linux_kernel	6.3 — 6.3.2

References

Advisories & Patches

https://git.kernel.org/stable/c/2322462d6f9ad4874f4e3c63df3b5cc00cb1acbd https://git.kernel.org/stable/c/4b8a05e3801661a0438fcd0cdef181030d966a5a https://git.kernel.org/stable/c/4fbefeab88c6e79753a25099d455d3d59d2946b4 https://git.kernel.org/stable/c/7041101ff6c3073fd8f2e99920f535b111c929cb https://git.kernel.org/stable/c/85f24cb2f10b2b0f2882e5786a09b4790bb3a0ad https://git.kernel.org/stable/c/d0b43125ec892aeb1b03e5df5aab595097da225a

Frequently Asked Questions

What is CVE-2023-53624? +

In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_fq: fix integer overflow of "credit" if sch_fq is configured with "initial quantum" having values greater than INT_MAX, the first assignment of "credit" does signed integer overflow to a very negative value. In this situation, the syzkaller script provided by Cristoph triggers the CPU soft-lockup warning even with few sockets. It's not an infinite loop, but "credit" wasn't probably meant to be minus 2Gb for each new flow. Capping "initial quantum" to INT_MAX proved to fix the issue. v2: validation of "initial quantum" is done in fq_policy, instead of open coding in fq_change() _ suggested by Jakub Kicinski It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2023-53624? +

CVE-2023-53624 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2023-53624? +

CVE-2023-53624 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-53624? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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