CVE-2023-3611 Out-of-bounds write in Linux kernel's net/sched: sch_qfq component

What is CVE-2023-3611?

CVE-2023-3611 is a high-severity memory corruption vulnerability in Debian Debian Linux, published on 21 Jul 2023. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

An out-of-bounds write vulnerability in the Linux kernel's net/sched: sch_qfq component can be exploited to achieve local privilege escalation.

The qfq_change_agg() function in net/sched/sch_qfq.c allows an out-of-bounds write because lmax is updated according to packet sizes without bounds checks.

We recommend upgrading past commit 3e337087c3b5805fe0b8a46ba622a962880b5d64.

Weakness: CWE-787

Which versions are affected by CVE-2023-3611?

It affects 2 products.

Products include Debian Debian Linux, Linux kernel.

How do I fix CVE-2023-3611?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2023-3611 being exploited?

There is no known exploitation of CVE-2023-3611 in the wild and no public exploit code.

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All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-27675, DEBIAN-CVE-2023-3611, GHSA-x5xp-6cpr-4xwx, UBUNTU-CVE-2023-3611.