CVE-2026-86871 An integer underflow was addressed with improved input validation.
Medium 5.9
Published
Updated
Check this codebase for CVE-2026-86871 and fix it if it is affected.
What it is: CVE-2026-86871 is a medium-severity vulnerability in Apple macOS, published on 20 Oct 2026.
Exploitation: There is no known exploitation of CVE-2026-86871 in the wild and no public exploit code.
Affected product: Apple macOS. 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-2026-86871/ (Markdown: https://insights.sbomify.com/CVE-2026-86871/index.md)
- Exploited in the wild
- Not known
- Fix
- None listed
What is CVE-2026-86871?
CVE-2026-86871 is a medium-severity vulnerability in Apple macOS, published on 20 Oct 2026.
Official description
An integer underflow was addressed with improved input validation. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7. An attacker with control of a network file server may be able to cause unexpected system termination.
Which versions are affected by CVE-2026-86871?
How do I fix CVE-2026-86871?
No fix has been published for CVE-2026-86871 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-86871 being exploited?
There is no known exploitation of CVE-2026-86871 in the wild and no public exploit code.
Sources
Also known as GHSA-g6m6-98mf-rjcv.