# CVE-2022-49776: macvlan: enforce a consistent minimal mtu

Status: published. Published: 2025-05-01. Updated: 2026-11-05.

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

macvlan: enforce a consistent minimal mtu

macvlan should enforce a minimal mtu of 68, even at link creation.

This patch avoids the current behavior (which could lead to crashes
in ipv6 stack if the link is brought up)

$ ip link add macvlan1 link eno1 mtu 8 type macvlan  # This should fail !
$ ip link sh dev macvlan1
5: macvlan1@eno1: <BROADCAST,MULTICAST> mtu 8 qdisc noop
    state DOWN mode DEFAULT group default qlen 1000
    link/ether 02:47:6c:24:74:82 brd ff:ff:ff:ff:ff:ff
$ ip link set macvlan1 mtu 67
Error: mtu less than device minimum.
$ ip link set macvlan1 mtu 68
$ ip link set macvlan1 mtu 8
Error: mtu less than device minimum.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Linux / Linux: ≥ 91572088e3fdbf4fe31cf397926d8b890fdb3237; < d2fee7d121d189c6dc905b727d60e7043a6655bb (affected, git); ≥ 91572088e3fdbf4fe31cf397926d8b890fdb3237; < 650137a7c0b2892df2e5b0bc112d7b09a78c93c8 (affected, git); ≥ 91572088e3fdbf4fe31cf397926d8b890fdb3237; < a62aa84fe19eb24d083d600a074c009a0a66d4f3 (affected, git); ≥ 91572088e3fdbf4fe31cf397926d8b890fdb3237; < e929ec98c0c3b10d9c07f3776df0c1a02d7a763e (affected, git); ≥ 91572088e3fdbf4fe31cf397926d8b890fdb3237; < e41cbf98df22d08402e65174d147cbb187fe1a33 (affected, git); ≥ 91572088e3fdbf4fe31cf397926d8b890fdb3237; < 2b055c719d8f94c15ec9b7659978133030c6a353 (affected, git); ≥ 91572088e3fdbf4fe31cf397926d8b890fdb3237; < b64085b00044bdf3cd1c9825e9ef5b2e0feae91a (affected, git). Source: CNA: Linux
- Linux / Linux: 4.10 (affected); ≥ 0; < 4.10 (unaffected, semver); ≥ 4.14.300; ≤ 4.14.* (unaffected, semver); ≥ 4.19.267; ≤ 4.19.* (unaffected, semver); ≥ 5.4.225; ≤ 5.4.* (unaffected, semver); ≥ 5.10.156; ≤ 5.10.* (unaffected, semver); ≥ 5.15.80; ≤ 5.15.* (unaffected, semver); ≥ 6.0.10; ≤ 6.0.* (unaffected, semver); ≥ 6.1; ≤ * (unaffected, original_commit_for_fix). Source: CNA: Linux

## Severity and prioritization

- CISA KEV: No listing in collected sources

- EPSS: 0.22% as of 2026-11-05; percentile 12.34%

- 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/d2fee7d121d189c6dc905b727d60e7043a6655bb (CNA: Linux)

- https://git.kernel.org/stable/c/650137a7c0b2892df2e5b0bc112d7b09a78c93c8 (CNA: Linux)

- https://git.kernel.org/stable/c/a62aa84fe19eb24d083d600a074c009a0a66d4f3 (CNA: Linux)

- https://git.kernel.org/stable/c/e929ec98c0c3b10d9c07f3776df0c1a02d7a763e (CNA: Linux)

- https://git.kernel.org/stable/c/e41cbf98df22d08402e65174d147cbb187fe1a33 (CNA: Linux)

- https://git.kernel.org/stable/c/2b055c719d8f94c15ec9b7659978133030c6a353 (CNA: Linux)

- https://git.kernel.org/stable/c/b64085b00044bdf3cd1c9825e9ef5b2e0feae91a (CNA: Linux)

## Provenance

- CNA: Linux: https://www.cve.org/CVERecord?id=CVE-2022-49776; retrieved 2026-11-05; source updated 2026-11-05

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2022-49776; retrieved 2026-11-05; source updated Not reported

Revision: 4e1017e9043b242d758d8d5db5792f15aa9291e3e01c69781c5fac0b89e1012b

Canonical: https://y2.dev/cve/CVE-2022-49776

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