CVE-2022-49325 tcp: add accessors to read/set tp->snd_cwnd

What is CVE-2022-49325?

CVE-2022-49325 is a high-severity denial of service vulnerability in Linux kernel, published on 26 Feb 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

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

tcp: add accessors to read/set tp->snd_cwnd

We had various bugs over the years with code breaking the assumption that tp->snd_cwnd is greater than zero.

Lately, syzbot reported the WARN_ON_ONCE(!tp->prior_cwnd) added in commit 8b8a321ff72c ("tcp: fix zero cwnd in tcp_cwnd_reduction") can trigger, and without a repro we would have to spend considerable time finding the bug.

Instead of complaining too late, we want to catch where and when tp->snd_cwnd is set to an illegal value.

Weakness: CWE-617

Which versions are affected by CVE-2022-49325?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2022-49325?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2022-49325 being exploited?

There is no known exploitation of CVE-2022-49325 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

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

Also known as DEBIAN-CVE-2022-49325, GHSA-qwqp-8pr4-72vm, ROOT-OS-DEBIAN-11-CVE-2022-49325, UBUNTU-CVE-2022-49325.