CVE-2026-92957
CVE-2026-92957 — vm2 before 3.11.7 Authentication Bypass via node: Prefix
vm2 through 3.11.6 does not normalize `node:`-prefixed builtin specifiers when evaluating user-supplied negative (deny) entries in a NodeVM wildcard require policy. Although NodeVM strips the `node:` prefix during require() resolution, negative wildcard entries are matched by exact string comparison against the canonical builtin names, so a policy such as `new NodeVM({ require: { builtin: ['*', '-node:child_process'] } })` fails to deny the canonical `child_process` module. Sandboxed code can therefore obtain the host `child_process` builtin via `require('child_process')` or `require('node:child_process')`, gaining references to process-spawning APIs such as execSync and spawn, which is equivalent to host command-execution capability for untrusted sandbox code. Fixed in vm2 3.11.7. (Suggested title: "vm2 before 3.11.7: NodeVM builtin deny-list bypass via node:-prefixed specifiers exposes child_process")
Published Updated Sources: NVD, patriksimek (CNA), GitHub, GitHub Security Advisory, SOCRadar CTI
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Exploit code
public exploit, none observed
EPSS
0%
ahead of 0% of scored CVEs
CVSS base
9.9
critical · 2 sources
Remediation
The vendor's own words where we have them.
Upgrade vm2 to a fixed release (3.11.7). Apply vendor patches per advisory and restrict external exposure of the affected component until patched.
First 24 hours
Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.
- Identify exposed assets running affected vendor/product/version combinations.
- Prioritize based on EPSS, PoC availability, and external exposure.
- Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.
Affected scope
Vendor, product and version as the advisories word them.
| Vendor | Product | Versions | Status |
|---|---|---|---|
| patriksimek | vm2 | 0 to < 3.11.7 | Vulnerable |
| patriksimek | vm2 | 3.11.7 | Patched |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Availability
High
Confidentiality
High
Integrity
High
Scope
Changed
Attack Complexity
Low
Attack Vector
Network
Privileges Req
Low
User Interaction
None
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 9.9 | CVSS 3.1 | critical | 3.1 | 6 | NVD, patriksimek (CNA), GHSA |
| 9.4 | CVSS 4.0 | critical | — | — | patriksimek (CNA) |
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
What this weakness leads to
MITRE's own consequences and mitigations for the weakness class — the authority's wording, not guidance derived from the CVSS vector.
CWE-269 · Improper Privilege Management
- Gain Privileges or Assume Identity::
Mitigation: Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
Weakness & attack patterns
- CWE-269Improper Privilege Management
Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.
- T1548Abuse Elevation Control Mechanism
Public exploit
Capability, not use: code existing is a different claim from anyone running it.
Repositories
1
Detection
Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.
- Prioritize edge telemetry for network-reachable vm2.
- Review endpoint telemetry for service binary replacement, suspicious service launches, or privilege changes tied to the affected agent.
- Monitor for scanner or exploit-pattern traffic after 1 public PoC repositories were reported.
Timeline
What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.
- 2026
Added · CVSS 3.1 9.9 (AV:N)
Sep 17, 2026 · NVD
Initial · CVE published
Sep 17, 2026 · NVD
Added · GHSA-28q4-xrqh-9479 published (critical)
Sep 17, 2026 · GitHub Security Advisory
CVE published by MITRE.
Sep 17, 2026 · SOCRadar CTI
References
4 on the record
- github.com/patriksimek/vm2/security/advisories/GHSA-8686-vhfx-7r3j
Exploit, Third Party Advisory, Mitre
- www.vulncheck.com/advisories/vm2-before-3.11.7-authentication-bypass-via-node-prefix
Vendor Advisory, Mitre
- nvd.nist.gov/vuln/detail/CVE-2026-92957
NVD
- github.com/advisories/GHSA-28q4-xrqh-9479
Exploit, Third Party Advisory
Elsewhere on this site
- patriksimekevery CVE for this vendor
- Privilege Escsame class
- CWE-269other pages naming this weakness
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record1
What should defenders know first?
CVE-2026-92957 is vm2 before 3.11.7 Authentication Bypass via node: Prefix, a critical vulnerability affecting vm2 from patriksimek. The current evidence does not list it in CISA KEV, and the exploit status is: Active exploitation is not confirmed from current sources for CVE-2026-92957. Public exploit evidence is: 1 public PoC repositories reported; 0 marked weaponized in current dataset. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS 9.9 describes technical severity, while EPSS 0% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.