CVE-2025-11919 — Default JVM Insecure Shared /tmp Handling Enables Classpath Hijacking (CVE-2025-11919)
The default JVM can access files and directories under `/tmp/` including the `$TemporaryDirectory` of other users on the same cloud instance (`/tmp/UserTemporaryFiles/`). The `-init` file for the the JVM initialization exists in the vulnerable directory during the startup of the JVM. An attacker with access to the shared `/tmp/` space can preemptively create or replace `.jar` files or directories (via the `-init` file) that the victim JVM will resolve first in its classpath. By strategically placing a malicious version of a commonly used library (e.g., `commons-io`) in a location that is included in the classpath before the legitimate version, an attacker can cause the JVM to load the malicious class during startup, thereby executing the attacker's code.
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 0.5% (30-day exploitation probability)+6
- Technical severity (critical)+10
- CISA SSVC: exploitation "poc"+5
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 (Wolfram Research Inc. Cloud).
- 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 |
|---|---|---|---|---|
| Wolfram Research Inc. | Cloud | version 14.2 | 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 |
|---|---|---|---|---|---|
| 9.6 | CVSS 3.1 | Critical | 3.1 | 5.8 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 via NIST National Vulnerability Database |
| 9.6 | CVSS 3.1 | Critical | — | — | CISA-ADP via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N (score shown at the top: 134c704f-9b21-4f2e-91b3-4a467353bcc0) EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.49%
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).
Analysis and videos
CVE-2025-11919: Default JVM Insecure Shared /tmp Handling Enables Classpath Hijacking
CVE-2025-11919 is a critical issue (CVSS 3.1 base score 9.6) in the default Java Virtual Machine, where files under the shared /tmp directory can influence which libraries the JVM loads from its classpath. The record does not name the affected product, versions, or a fixed version. No confirmed exploitation appears in the sources consulted.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · wolfram research inc./cloud
- SSVC assessment updated
- Record published
- CVSS changed · 9.6
- Source status changed · → Awaiting Analysis
- 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
2 on the record
Elsewhere on this site
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 CWE classification.
- 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-2025-11919 is "Default JVM Insecure Shared /tmp Handling Enables Classpath Hijacking (CVE-2025-11919)", rated Critical. It affects Cloud (Wolfram Research Inc.); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 9.6 describes technical severity. EPSS 0.49% 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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