Security readout for executives and security teams
Plain-English summary
CVE-2026-21942 is a denial-of-service vulnerability in Oracle Solaris filesystems. A low-privileged logged-in user could cause the Solaris system to hang or crash repeatedly, but the attack requires another person’s interaction. The main business risk is service outage, not data theft or tampering.
Executive priority
Treat as a scheduled but important availability fix for Solaris environments. Prioritize internet-facing infrastructure dependencies, shared Solaris hosts, and business-critical systems where local users have access. No evidence provided indicates data exposure or active exploitation.
Technical view
Oracle reports an easily exploitable local vulnerability in Oracle Solaris 10 and 11, Filesystems component. CVSS 3.1 is 5.0 with local access, low complexity, low privileges, required user interaction, unchanged scope, and high availability impact only. The associated weakness is CWE-400 resource consumption.
Likely exposure
Exposure is limited to Oracle Solaris 10 or 11 systems where untrusted or low-privileged users can log on. Systems with many shell users, shared administration access, or interactive application accounts have higher practical exposure.
Exploitation context
The source bundle does not show active exploitation, and CISA KEV is false. Exploitation requires local logon and human interaction by someone other than the attacker. Public sources provided do not include exploit details.
Researcher notes
The vulnerability is local, authenticated, and availability-only per Oracle’s CVSS vector. Required user interaction is a key limiting factor. The public source bundle does not identify the exact filesystem flaw, vulnerable code path, or exploit prerequisites beyond Oracle’s advisory metadata.
Mitigation direction
- Review Oracle’s January 2026 Critical Patch Update for Solaris guidance.
- Apply applicable Oracle Solaris security updates or patches from Oracle.
- Restrict local logon access to trusted users only.
- Monitor Solaris systems for unexpected hangs, crashes, or repeatable availability failures.
Validation and detection
- Inventory Oracle Solaris 10 and 11 systems.
- Confirm whether the Filesystems component is present on affected hosts.
- Check installed Solaris patch levels against Oracle CPU January 2026 guidance.
- Review logs and uptime data for repeated crashes or hangs.
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-400: 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 lookupCVE-2026-21942 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
- Medium
- CVSS
- 5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:N/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.
CVSS vector scores
1 official scoreWe 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:L/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H1.33.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5MediumVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- Oracle AdvisoryCVE reference · vendor-advisory
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.
Uncontrolled Resource Consumption
Uncontrolled Resource Consumption represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.