What’s Vulnerable › Vulnerabilities

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

• Severity: medium (CVSS 5.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.6% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2025-02-26 · updated 2026-08-04
• Weakness: CWE-617

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.

Affected products

• Linux kernel: before 5.15.47; from 5.16 before 5.17.15; from 5.18 before 5.18.4 — fixed in 5.15.47, 5.17.15, 5.18.4

How to fix

Upgrade to a fixed version: Linux kernel 5.15.47, 5.17.15, 5.18.4. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/3308676ec525901bf1656014003c443a60730a04
• https://git.kernel.org/stable/c/40570375356c874b1578e05c1dcc3ff7c1322dbe
• https://git.kernel.org/stable/c/41e191fe72282e193a7744e2fc1786b23156c9e4
• https://git.kernel.org/stable/c/5aba0ad44fb4a7fb78c5076c313456de199a3c29

Get alerted when CVE-2022-49325 or the next vulnerability affects your stack