# CVE-2026-72349: netfilter: xt_rateest: fix u64 truncation in xt_rateest_mt()

Status: published. Published: 2026-08-15. Updated: 2026-11-06.

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

netfilter: xt_rateest: fix u64 truncation in xt_rateest_mt()

On links faster than ~34 Gbps, where byte rate may exceed 2^32-1
(~ 4.3 GBps), the comparison result becomes incorrect because the
truncated value no longer reflects the actual estimator rate.

Fix by changing the local variables to u64.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Linux / Linux: ≥ 1c0d32fde5bdf1184bc274f864c09799278a1114; < 77e9ba358d63fe2eb03c90d29ea85651d95cf2e6 (affected, git); ≥ 1c0d32fde5bdf1184bc274f864c09799278a1114; < a3ba938f45cb00f6bf49d3aa3647df9b017f5f08 (affected, git); ≥ 1c0d32fde5bdf1184bc274f864c09799278a1114; < bab305dd769d78074adca73505cc2509e1206bf2 (affected, git); ≥ 1c0d32fde5bdf1184bc274f864c09799278a1114; < 5da915fc159c6b4091669447588e520183969cca (affected, git); ≥ 1c0d32fde5bdf1184bc274f864c09799278a1114; < d5cc4c12a4b90bf099199c3c49ecda7e694f2a2b (affected, git); ≥ 1c0d32fde5bdf1184bc274f864c09799278a1114; < e702f6dd5d21e331f55fd9168c0210542008546d (affected, git); ≥ 1c0d32fde5bdf1184bc274f864c09799278a1114; < 905a927b2e6fec7b174e9e5644d271047b61378f (affected, git); ≥ 1c0d32fde5bdf1184bc274f864c09799278a1114; < 444853cd438201007da5359821adcc2995655ab1 (affected, git). Source: CNA: Linux
- Linux / Linux: 4.10 (affected); ≥ 0; < 4.10 (unaffected, semver); ≥ 5.10.261; ≤ 5.10.* (unaffected, semver); ≥ 5.15.212; ≤ 5.15.* (unaffected, semver); ≥ 6.1.178; ≤ 6.1.* (unaffected, semver); ≥ 6.6.145; ≤ 6.6.* (unaffected, semver); ≥ 6.12.97; ≤ 6.12.* (unaffected, semver); ≥ 6.18.40; ≤ 6.18.* (unaffected, semver); ≥ 7.1.5; ≤ 7.1.* (unaffected, semver); ≥ 7.2; ≤ * (unaffected, original_commit_for_fix). Source: CNA: Linux

## Severity and prioritization

- CISA KEV: No listing in collected sources

- EPSS: 0.22% as of 2026-11-06; percentile 12.61%

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: Not reported

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://git.kernel.org/stable/c/77e9ba358d63fe2eb03c90d29ea85651d95cf2e6 (CNA: Linux)

- https://git.kernel.org/stable/c/a3ba938f45cb00f6bf49d3aa3647df9b017f5f08 (CNA: Linux)

- https://git.kernel.org/stable/c/bab305dd769d78074adca73505cc2509e1206bf2 (CNA: Linux)

- https://git.kernel.org/stable/c/5da915fc159c6b4091669447588e520183969cca (CNA: Linux)

- https://git.kernel.org/stable/c/d5cc4c12a4b90bf099199c3c49ecda7e694f2a2b (CNA: Linux)

- https://git.kernel.org/stable/c/e702f6dd5d21e331f55fd9168c0210542008546d (CNA: Linux)

- https://git.kernel.org/stable/c/905a927b2e6fec7b174e9e5644d271047b61378f (CNA: Linux)

- https://git.kernel.org/stable/c/444853cd438201007da5359821adcc2995655ab1 (CNA: Linux)

- https://git.kernel.org/stable/c/444853cd438201007da5359821adcc2995655ab1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)

- https://git.kernel.org/stable/c/5da915fc159c6b4091669447588e520183969cca (416baaa9-dc9f-4396-8d5f-8c081fb06d67)

- https://git.kernel.org/stable/c/77e9ba358d63fe2eb03c90d29ea85651d95cf2e6 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)

- https://git.kernel.org/stable/c/905a927b2e6fec7b174e9e5644d271047b61378f (416baaa9-dc9f-4396-8d5f-8c081fb06d67)

- https://git.kernel.org/stable/c/a3ba938f45cb00f6bf49d3aa3647df9b017f5f08 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)

- https://git.kernel.org/stable/c/bab305dd769d78074adca73505cc2509e1206bf2 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)

- https://git.kernel.org/stable/c/d5cc4c12a4b90bf099199c3c49ecda7e694f2a2b (416baaa9-dc9f-4396-8d5f-8c081fb06d67)

- https://git.kernel.org/stable/c/e702f6dd5d21e331f55fd9168c0210542008546d (416baaa9-dc9f-4396-8d5f-8c081fb06d67)

## Provenance

- CNA: Linux: https://www.cve.org/CVERecord?id=CVE-2026-72349; retrieved 2026-11-06; source updated 2026-11-06

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-72349; retrieved 2026-11-06; source updated 2026-11-06

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-72349; retrieved 2026-11-06; source updated Not reported

Revision: bc6212cf19844dde7286451c1f60b92fadb03d436ab6169a8f952a21e15e2c2b

Canonical: https://y2.dev/cve/CVE-2026-72349

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