CVE-2026-123203
NEURON through 9.0.2 Stack-based Buffer Overflow via CoreNEURON dataset tokens
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Passive
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
6.9
NEURON through 9.0.2 Stack-based Buffer Overflow via CoreNEURON dataset tokens
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.
- Record
CVE-2026-123203- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H - Weakness
- CWE-121
- Updated
- 2026-11-05
EUVDEUVD-2026-117648
6.9
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.
- Record
EUVD-2026-117648- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-06
GitHub AdvisoriesGHSA-qgg2-74c2-x77r
6.9
NEURON (CoreNEURON) through 9.0.2 contains a stack buffer overflow vulnerability that allows...
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.
- Record
GHSA-qgg2-74c2-x77r- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H - Weakness
- CWE-121
- Updated
- 2026-11-05
NVD
6.9
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.
- Record
CVE-2026-123203- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H - Weakness
- CWE-121
- Updated
- 2026-11-05
OSV
6.9
NEURON through 9.0.2 Stack-based Buffer Overflow via CoreNEURON dataset tokens
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.
- Record
CVE-2026-123203- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-121
- Updated
- 2026-11-07
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| published | EUVD | |
| published | EUVD | |
| references | OSV | |
| aliases, references | GitHub Advisories, NVD | |
| cwes, products, references, severity, title | CVE List | |
| first indexed | EUVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-123203 is a medium vulnerability (CVSS 6.9) in Emqx Neuron, published November 5, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.14%, the 3rd percentile. No source names a fixed version.
References
github.com/neuronsimulator/nrn/pull/3932
github.com/neuronsimulator/nrn/commit/6e5a6578a3503c44ee0f19593e7ffb19812ef0e1
github.com/neuronsimulator/nrn/blob/ba5783378c0aa1d9ac95b4454bea94b15c63f75d/src/coreneuron/io/mk_mech.cpp
vulncheck.com/advisories/neuron-through-9.0.2-stack-based-buffer-overflow-via-coreneuron-dataset-tokens
nvd.nist.gov/vuln/detail/CVE-2026-123203
github.com/advisories/GHSA-qgg2-74c2-x77r
github.com/CVEProject/cvelistV5/tree/main/cves/2026/123xxx/CVE-2026-123203.json
github.com/neuronsimulator/nrn