# CVE-2026-98497: net/mlx5e: fix swapped IPv6 IPsec policy masks

> A bug in the Linux kernel mlx5e driver swaps IPv6 IPsec policy masks, allowing attackers to bypass IPsec security policies when prefix lengths differ.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 18 Oct 2026
- **Updated:** 24 Oct 2026
- **Also known as:** BELL-CVE-2026-98497, DEBIAN-CVE-2026-98497, GHSA-jq4w-vj6x-gwh6, UBUNTU-CVE-2026-98497

## What is CVE-2026-98497?

CVE-2026-98497 is a high-severity vulnerability in Linux, published on 18 Oct 2026. 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:

net/mlx5e: fix swapped IPv6 IPsec policy masks

IPv6 XFRM policies may use different source and destination prefix
lengths. mlx5e_ipsec_policy_mask() builds the corresponding masks
independently, but setup_fte_addr6() installs each mask in the opposite
address field.

When the prefix lengths differ, this makes the source match use the
destination prefix and the destination match use the source prefix. The
resulting hardware rule can both miss traffic covered by the policy and
match traffic outside it.

Install each mask in its corresponding match field.

## Which versions are affected by CVE-2026-98497?


## How do I fix CVE-2026-98497?

Apply the vendor's patch.

## Is CVE-2026-98497 being exploited?

There is no known exploitation of CVE-2026-98497 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98497 and fix it if it is affected.

What it is: CVE-2026-98497 is a high-severity vulnerability in Linux, published on 18 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-98497 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-98497/ (Markdown: https://insights.sbomify.com/CVE-2026-98497/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98497
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98497
- OSV: https://osv.dev/vulnerability/CVE-2026-98497

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98497/
Summaries are generated and may contain mistakes; the official description above is the record.