What is CVE-2026-47683?

CVE-2026-47683 is vm2: bufferAllocLimit cap bypassed by Buffer.concat and Buffer.from arrayLike. The supplied enrichment data classifies it as Remote Code Exec mapped to CWE-770 CWE-770.

Which versions are affected?

Affected product and version evidence is listed in the product table above. Current public advisories should be checked for exact version scope before patch targeting is finalized.

Is there active exploitation?

Active exploitation is not confirmed from current sources for CVE-2026-47683. If exploitation is not confirmed from current sources, teams should document that status and continue monitoring KEV, vendor, and telemetry updates.

No. CVE-2026-47683 is not listed in CISA KEV in the supplied enrichment data. KEV status should be monitored because it can change after initial disclosure or after exploitation becomes publicly confirmed.

Is there a public exploit?

2 public PoC repositories reported; 0 marked weaponized in current dataset. Public exploit or PoC availability should raise triage priority, especially for exposed or business-critical systems.

How can defenders detect it?

Start with EDR process telemetry, host service logs where available. Look for vulnerability-class behavior, product errors, suspicious authentication events, exploit probes, and abnormal process activity based only on evidence that applies to the affected product.

How should teams prioritize it?

Prioritize CVE-2026-47683 using CVSS 8.7, EPSS 0%, KEV status, public PoC status, and asset exposure. Internet-facing, privileged, or business-critical deployments should be handled first.

Are workarounds available?

Workarounds are not confirmed from current sources. Fixed-version evidence is listed in the mitigation section above.

Which threat actors are linked publicly?

No public threat actor linkage is confirmed from current sources. Do not attribute exploitation to a threat actor unless the source evidence explicitly supports that linkage.

What should be done in the next 24 hours?

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. Open remediation tickets with affected assets, owners, evidence status, and detection coverage so decisions are traceable.

highRemote Code Execpublic exploit

CVE-2026-47683

CVE-2026-47683 — vm2: bufferAllocLimit cap bypassed by Buffer.concat and Buffer.from arrayLike

vm2 is an open source vm/sandbox for Node.js. Prior to 3.11.6, the bufferAllocLimit enforcement in lib/setup-sandbox.js does not cover Buffer.concat(list, totalLength) or Buffer.from(arrayLike) with an attacker-controlled length, allowing sandbox code to perform large synchronous host external-memory allocations that bypass the configured cap and can exhaust the host process. This issue is fixed in version 3.11.6.

Published Aug 17, 2026Updated Aug 17, 2026Sources: 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

ahead of 0% of scored CVEs

Affects

patriksimek

2 products listed

CVSS base

8.7

high

Remediation

The vendor's own words where we have them.

Upgrade vm2 to 3.11.6 or later (npm advisory GHSA-gmc2-2x9w-cgh9).

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	< 3.11.6	Vulnerable
npm	vm2	<= 3.11.5	Vulnerable

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
8.7	CVSS 4.0	high	—	—	patriksimek (CNA)

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

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.

MITRE

CWE-770 · Allocation of Resources Without Limits or Throttling

DoS: Resource Consumption (CPU)
DoS: Resource Consumption (Memory)
DoS: Resource Consumption (Other)

Mitigation: Clearly specify the minimum and maximum expectations for capabilities, and dictate which behaviors are acceptable when resource allocation reaches limits.

Weakness & attack patterns

CWE-770

Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.

CAPEC-528 · XML FloodCAPEC-230 · XML Nested PayloadsCAPEC-496 · ICMP FragmentationCAPEC-493 · SOAP Array BlowupCAPEC-487 · ICMP FloodCAPEC-147 · XML Ping of the DeathCAPEC-495 · UDP FragmentationCAPEC-486 · UDP FloodCAPEC-489 · SSL FloodCAPEC-469 · HTTP DoSCAPEC-231 · Oversized Serialized Data PayloadsCAPEC-494 · TCP Fragmentation

T1498.001Network Denial of Service: Direct Network Flood
T1499Endpoint Denial of Service
T1499.003Endpoint Denial of Service: Application Exhaustion Flood

Public exploit

Capability, not use: code existing is a different claim from anyone running it.

Repositories

Detection

Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.

Search application, proxy, and WAF logs for requests touching /sandbox, /setup-sandbox.js.
Monitor for scanner or exploit-pattern traffic after 2 public PoC repositories were reported.

EDR process telemetryhost service logs

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 8.7
Aug 17, 2026 · NVD
Initial · CVE published
Aug 17, 2026 · NVD
Added · GHSA-gmc2-2x9w-cgh9 published (high)
Aug 17, 2026 · GitHub Security Advisory

References

4 on the record

github.com/patriksimek/vm2/commit/3ffb315512e634cf85c447375e85d6c83d00a4bd
Exploit, Third Party Advisory, Mitre
github.com/patriksimek/vm2/releases/tag/3.11.6
Exploit, Third Party Advisory, Mitre
github.com/patriksimek/vm2/security/advisories/GHSA-gmc2-2x9w-cgh9
Exploit, Third Party Advisory, Mitre
github.com/advisories/GHSA-gmc2-2x9w-cgh9
Exploit, Third Party Advisory

Elsewhere on this site

patriksimekevery CVE for this vendor
npmevery CVE for this vendor
Remote Code Execsame class
CWE-770other 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-2026-47683 is vm2: bufferAllocLimit cap bypassed by Buffer.concat and Buffer.from arrayLike, a high vulnerability affecting vm2 from patriksimek, npm. 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-2026-47683. Public exploit evidence is: 2 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 8.7 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.