CVE-2026-123203 NEURON through 9.0.2 Stack-based Buffer Overflow via CoreNEURON dataset tokens
Medium 6.9
Published
Updated
Check this codebase for CVE-2026-123203 and fix it if it is affected.
What it is: CVE-2026-123203 is a medium-severity vulnerability in neuronsimulator NEURON, published on 5 Nov 2026.
Exploitation: There is no known exploitation of CVE-2026-123203 in the wild and no public exploit code.
Affected product: neuronsimulator NEURON. 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-2026-123203/ (Markdown: https://insights.sbomify.com/CVE-2026-123203/index.md)
- Exploited in the wild
- Not known
- Fix
- None listed
What is CVE-2026-123203?
CVE-2026-123203 is a medium-severity vulnerability in neuronsimulator NEURON, published on 5 Nov 2026.
Official description
NEURON (CoreNEURON) through 9.0.2 contains a stack buffer overflow vulnerability that allows attackers to corrupt stack memory by supplying over-long tokens in a crafted model dataset. Attackers can place oversized version or mechanism-name tokens in bbcore_mech.dat, globals.dat, or files.dat loaded by nrniv-core to crash the process.
Weakness: CWE-121
Which versions are affected by CVE-2026-123203?
How do I fix CVE-2026-123203?
No fix has been published for CVE-2026-123203 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-123203 being exploited?
There is no known exploitation of CVE-2026-123203 in the wild and no public exploit code.
Sources
Also known as GHSA-qgg2-74c2-x77r.