Security readout for executives and security teams
Plain-English summary
CVE-2026-26956 is a critical sandbox escape in vm2 3.10.4, limited by the source bundle to Node.js 25. Code intended to be confined inside vm2 can break out and execute with the host process's authority. Any service using vm2 to run untrusted JavaScript should treat this as urgent.
Executive priority
Treat as an emergency fix for systems that run untrusted code with vm2 on Node.js 25. The business risk is host compromise from a component specifically intended to isolate code. Patch quickly, validate deployment, and confirm whether any externally reachable workflow can trigger vm2 execution.
Technical view
The advisory describes full sandbox escape and arbitrary code execution from attacker-controlled code passed to VM.run(). The affected package is patriksimek/vm2 version 3.10.4, with a fix in 3.10.5. CVSS is 9.8: network attack vector, low complexity, no privileges, no user interaction, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is most likely in applications or platforms that run untrusted JavaScript through vm2 3.10.4 on Node.js 25. Risk is lower where vm2 is absent, upgraded, unused for untrusted code, or not running on Node.js 25. Red Hat product exposure should be checked against its linked CVE and VEX records.
Exploitation context
The bundle states attacker code inside VM.run() can obtain the host process object and run host commands without host cooperation. KEV is false, and the provided sources do not establish active exploitation in the wild. Public exploit availability is not confirmed by the supplied evidence.
Researcher notes
Core facts are source-grounded: affected version 3.10.4, patch 3.10.5, Node 25 scope, CVSS 9.8, CWE-653 and CWE-693. The sources do not provide exploit telemetry, proof of KEV listing, or detailed downstream affected-product mapping. Avoid assuming older vm2 lines or non-Node-25 runtimes are affected from this bundle alone.
Mitigation direction
- Upgrade vm2 from 3.10.4 to 3.10.5 or later where available.
- Prioritize services executing untrusted JavaScript through VM.run().
- Confirm deployed artifacts use the patched dependency, not only source manifests.
- Review vendor guidance for downstream packages and Red Hat applicability.
- Reduce or suspend untrusted-code execution until patched if immediate upgrade is blocked.
Validation and detection
- Search dependency manifests, lockfiles, SBOMs, and containers for vm2 3.10.4.
- Confirm affected services are running, or could run, on Node.js 25.
- Identify code paths that pass untrusted input into VM.run().
- Verify production images and runtime bundles contain vm2 3.10.5 or later.
- Check vendor advisories for distribution-specific status and backports.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-653: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCWE-693: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupPrivilege behavior lookup
The CVE wording references privilege impact, so privilege escalation and authorization behavior review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-26956 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
2 official scoresWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9GitHub_MCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9redhat-SADPVulnerability scoring details
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- ADP timelineredhat-SADP
Made public.
- CVE publishedCVE Program
The CVE record was published.
- ADP timelineredhat-SADP
Reported to Red Hat.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
- 2026-05-04T19:04:30.765Z: Reported to Red Hat.
- 2026-05-04T16:37:31.538Z: Made public.
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/patriksimek/vm2/security/advisories/GHSA-ffh4-j6h5-pg66CVE reference, GitHub_M · x_refsource_CONFIRM
- https://github.com/patriksimek/vm2/releases/tag/v3.10.5CVE reference, GitHub_M · x_refsource_MISC
- https://access.redhat.com/security/cve/CVE-2026-26956CVE reference, redhat-SADP · vdb-entry, x_refsource_REDHAT
- RHBZ#2466548CVE reference, redhat-SADP · issue-tracking, x_refsource_REDHAT
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-26956.jsonCVE reference, redhat-SADP · x_sadp-csaf-vex
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Isolation or Compartmentalization
Improper Isolation or Compartmentalization represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Protection Mechanism Failure
Protection Mechanism Failure represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.