CVE-2026-23919 — Insufficient isolation of JavaScript (Duktape) execution context on Zabbix Server
For performance reasons Zabbix Server/Proxy reuses JavaScript (Duktape) contexts (used in script items, JavaScript reprocessing, Webhooks). This can lead to confidentiality loss where a regular (non-super) Zabbix administrator leaks data for hosts they do not have access to. A fix has been released that makes the built in Zabbix JavaScript objects read-only, but please be advised that usage of global JavaScript variables is not recommended because their content could be leaked. More information <a href='https://www.zabbix.com/documentation/7.4/en/manual/installation/known_issues#preprocessing-global-variables-are-unsafe'>in Zabbix documentation</a>.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+2
- Technical severity (medium)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Zabbix Zabbix).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Zabbix | Zabbix | ≥ 6.0.0 and < 6.0.42≥ 7.0.0 and < 7.0.19≥ 7.2.0 and < 7.2.13≥ 7.4.0 and < 7.4.3 | Vulnerable | NIST National Vulnerability Database |
| Zabbix | Zabbix | ≥ 6.0.0 and ≤ 6.0.41≥ 7.0.0 and ≤ 7.0.18≥ 7.2.0 and ≤ 7.2.12≥ 7.4.0 and ≤ 7.4.2 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.1 | CVSS 4.0 | High | — | — | security@zabbix.com via NIST National Vulnerability Database |
| 7.1 | CVSS 4.0 | High | — | — | Zabbix via CVE Program (cve.org) e CISA ADP |
| 6.0 | CVSS 3.1 | Medium | 1.2 | 4.7 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:L/A:L (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.24%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · zabbix/zabbix
- SSVC assessment updated
- Record published
- CVSS changed · 6.0
- Source status changed · → Analyzed
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
1 on the record
Elsewhere on this site
Related CVEs (same products)
- Medium CVE-2026-59788 Stored XSS vulnerability in OAuth configuration form 10d
- Low CVE-2026-59783 Server DoS via binary items 10d
- Medium CVE-2026-59785 Hidden host credentials inferable via multiselect.get filtering 10d
- Medium CVE-2026-59786 Active agent heartbeat missing TLS check 10d
- Medium CVE-2026-59782 JavaScript preprocessing memory disclosure 10d
- Medium CVE-2026-59787 SNMP trap injection in zabbix_trap_receiver.pl 10d
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 fixed version, patch or mitigation documented.
- 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 record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-23919 is "Insufficient isolation of JavaScript (Duktape) execution context on Zabbix Server", rated Medium. It affects Zabbix (Zabbix); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 6.0 describes technical severity. EPSS 0.24% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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