SolarisOperating system · Oracle

CVE-2026-21928

MEDIUM · 5.3 CVSS v3.1 Published 2026-01-20
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
62/100
Remediation priority · Elevated
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Vulnerability in the Oracle Solaris product of Oracle Systems (component: Kernel). The supported version that is affected is 11. Easily exploitable vulnerability allows unauthenticated attacker with network access via TCP to compromise Oracle Solaris. Successful attacks of this vulnerability can result in unauthorized read access to a subset of Oracle Solaris accessible data. CVSS 3.1 Base Score 5.3 (Confidentiality impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N).

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

Kernel-level information disclosure vulnerability in Oracle Solaris 11. An unauthenticated remote attacker with network access via TCP can exploit this to read sensitive data that should not be accessible, leveraging a flaw in the Kernel component.

MitigationApply Oracle's security patches for CVE-2026-21928 when released. Until then, restrict network access to Solaris systems via firewalls or network segmentation to limit TCP exposure.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
SolarisOperating system
Affected:= 11

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the Oracle Solaris version
    Run 'uname -a' or 'cat /etc/release' to confirm the operating system is Oracle Solaris 11
    Affected if The system is not Oracle Solaris 11.x
  2. Determine the specific Solaris 11 release
    Run 'cat /etc/release' or 'showrev -p' to identify the exact Solaris 11 update release (e.g., Solaris 11.4, Solaris 11.3)
    Affected if The installed version matches Oracle Solaris 11 (exact version as specified in affected products)
  3. Verify TCP network exposure
    Run 'netstat -an | grep LISTEN' or 'svcs -a | grep network' to list listening TCP services
    Affected if Any TCP-based network services are listening and accessible from untrusted networks
  4. Confirm network accessibility
    Check firewall rules with 'ipf -V' or 'zonecfg' for non-global zones, and verify if the system is directly exposed to network by reviewing network interfaces with 'ifconfig -a'
    Affected if The system has TCP network access reachable from untrusted or public networks without proper firewall filtering
  5. Review applied Oracle security patches
    Run 'showrev -p' to list installed patches, then cross-reference with Oracle Critical Patch Updates for CVE-2026-21928
    Affected if No Oracle security patch for CVE-2026-21928 has been applied

You are affected if running Oracle Solaris 11 with any accessible TCP network services and without the Oracle security patch for this CVE.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply Oracle's security patches for CVE-2026-21928 when released. Until then, restrict network access to Solaris systems via firewalls or network segmentation to limit TCP exposure.

Fix this in Solaris Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA2.0 h
20.0 hours of engineering $3,500
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Scan for this in your stack

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dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-21928 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data