What’s Vulnerable › Vulnerabilities

CVE-2026-45897: netfilter: nft_counter: serialize reset with spinlock

• Severity: medium (CVSS 5.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-05-27 · updated 2026-09-14

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_counter: serialize reset with spinlock Add a global static spinlock to serialize counter fetch+reset operations, preventing concurrent dump-and-reset from underrunning values. The lock is taken before fetching the total so that two parallel resets cannot both read the same counter values and then both subtract them. A global lock is used for simplicity since resets are infrequent. If this becomes a bottleneck, it can be replaced with a per-net lock later.

Affected products

• Linux kernel: from 6.1.107 before 6.2; from 6.6.48 before 6.19.4 — fixed in 6.19.4, 6.2

How to fix

Upgrade to a fixed version: Linux kernel 6.19.4, 6.2. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/0cdc6d5a26f2d1f7f15a43526841b679445c32e2
• https://git.kernel.org/stable/c/48cf7918d10c66cb6b05226fa3fa5daf0c891089
• https://git.kernel.org/stable/c/779c60a5190c42689534172f4b49e927c9959e4e
• https://git.kernel.org/stable/c/cd968dcdec6aee79a2d399e4f6e0eca63c3b45e1
• https://git.kernel.org/stable/c/de6601f1374fab124cd9276df6671f64d940ceb4
• https://git.kernel.org/stable/c/e13194e60217db02c2e7202375d9e5951267d87b

Get alerted when CVE-2026-45897 or the next vulnerability affects your stack