Secuno
ENNL
Book demo

CVE-2026-43898

Nyariv Sandboxjs code injection

10.0 CRITICALPublic exploitEPSS 0.63%
  1. Published28 May 2026

Description

SandboxJS is a JavaScript sandboxing library. Prior to 0.9.6, sandbox-defined functions expose Function.caller, allowing sandboxed code to recover the internal LispType.Call runtime callback. That callback can then be invoked with attacker-controlled fake context and obj values to extract blocked host statics, recover the real host Function constructor, and execute arbitrary host JavaScript. This vulnerability is fixed in 0.9.6.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeChanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Affected products

Nyariv Sandboxjs< 0.9.6

Remediation

Fixed in
Nyariv Sandboxjs≥ 0.9.6

References

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

CVE-2026-891079.9
SAP S/4HANA (Manage Substitution/Validation Rules) does not sufficiently validate input…
CVE-2026-961199.9
IBM i 7.3, 7.4, 7.5, and 7.6 could allow a remote authenticated attacker to obtain…
CVE-2026-821088.8
IBM DataStage on Cloud Pak for Data 5.4.0.0 could allow a remote authenticated attacker…
CVE-2026-909209.8
IBM Maximo AI Service 9.1.0, and 9.2.0 could allow a remote attacker to execute…
CVE-2026-185378.7
IBM Maximo Application Suite - Location Service for Esri Component 9.2, 9.1, and 9.0 is…
CVE-2026-1093088.8
Craft CMS 4.0.0 before 4.18.7 and 5.0.0 before 5.10.14 passes the raw 'updates' request…

Frequently asked

Is CVE-2026-43898 being actively exploited?

CVE-2026-43898 is not in the CISA KEV catalog. A public exploit reference exists, so treat it as exploitable. Its EPSS exploit probability is 0.63%.

How severe is CVE-2026-43898?

CVE-2026-43898 has a CVSS 3.1 base score of 10.0, rated critical. EPSS estimates a 0.63% probability of exploitation.

Which products are affected by CVE-2026-43898?

Affected products include Nyariv Sandboxjs.

How do I fix CVE-2026-43898?

Upgrade affected software to a fixed version, for example Nyariv Sandboxjs 0.9.6 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-43898 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

See how prioritisation worksBook a demo

Get Patch this first every Monday

Five vulnerabilities that matter this week, ranked on real exploitation. Plain language, one email, no spam.

You can unsubscribe with one click from every issue. We handle your details as described in our privacy policy.

Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.