Is there a public exploit for CVE-2026-123203?

No public exploit for CVE-2026-123203 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-123203?

CVE-2026-123203 scores CVSS 6.9 (v4.0), rated medium.

What does CVE-2026-123203 affect?

CVE-2026-123203 affects neuronsimulator neuron.

6.9 Medium

NEURON (CoreNEURON) through 9.0.2 contains a stack buffer overflow vulnerability that allows attackers to corrupt stack memory by supplying…

CVE-2026-123203

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 bbcoremech.dat, globals.dat, or files.dat loaded by nrniv-core to crash the process.

Assessment

CVSS: 6.9 (v4.0)
Severity: Medium
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 5 November 2026
Last updated: 5 November 2026
Affected: neuronsimulator · neuron
Assigner: VulnCheck

CVSS vectorCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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