# CVE-2026-112158: MikroTik RouterOS ipt_SAME.ko same_check integer overflow

> A remote attacker can trigger an integer overflow in the ipt_SAME.ko module, potentially causing a denial of service on MikroTik RouterOS devices.

- **Severity:** High 7.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 19 Oct 2026
- **Updated:** 19 Oct 2026
- **Also known as:** GHSA-99hw-pp85-5wcr

## What is CVE-2026-112158?

CVE-2026-112158 is a high-severity vulnerability in MikroTik RouterOS, published on 19 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A weakness has been identified in MikroTik RouterOS up to 6.40.5/6.44/7.20.8. Impacted is the function same_check of the file ipt_SAME.ko. Executing a manipulation can lead to integer overflow. The attack may be launched remotely. Upgrading to version 7.21.5 and 7.23.1 is recommended to address this issue. You should upgrade the affected component.

Weakness: CWE-190 (Integer Overflow or Wraparound), CWE-189

## Which versions are affected by CVE-2026-112158?


## How do I fix CVE-2026-112158?

No fix has been published for CVE-2026-112158 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-112158 being exploited?

There is no known exploitation of CVE-2026-112158 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-112158 and fix it if it is affected.

What it is: CVE-2026-112158 is a high-severity vulnerability in MikroTik RouterOS, published on 19 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-112158 in the wild and no public exploit code.

Affected product: MikroTik RouterOS. 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-2026-112158/ (Markdown: https://insights.sbomify.com/CVE-2026-112158/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-112158
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-112158
- OSV: https://osv.dev/vulnerability/CVE-2026-112158

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-112158/
Summaries are generated and may contain mistakes; the official description above is the record.