NVD / CVE Program· CNA dell

CVE-2026-21418: Dell Unity, version(s) 5.5.2 and prior, contain(s) an Improper Neutralization of Special Elements used in an OS Command ('OS Command…

HighCVSS 7.8 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 31/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.65% (FIRST EPSS); higher than 51.6% of all records.
Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
Fixed version: Dell Unity 5.5.3.

Low priority for now. Upgrade to Dell Unity 5.5.3 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Dell Unity, version(s) 5.5.2 and prior, contain(s) an Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') vulnerability. A low privileged attacker with local access could potentially exploit this vulnerability, leading to arbitrary command execution with root privileges.

Published: Jan 30, 2026
Updated: Jun 17, 2026
EPSS: 0.6% · 51th percentile
CWE: CWE-78

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 31 / 40 · 7.8 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.6%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · dell: 7.8; NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Is your version affected? Check it

Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
dell	unity operating environment	cpe:2.3:a:dell:unity_operating_environment

Versions reported by the vendor

Affected version ranges reported by the assigning authority (dell). Independent of NVD's CPE analysis and usually ahead of it.

Dell Unity
- N/A and later · before 5.5.3affected · semver

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

dell unity operating environmentbefore 5.5.3.0

Same product

dell: all records

Other highest-scoring records for the same primary product.

CVE-2025-36604Dell Unity, version(s) 5.5 and prior, contain(s) an Improper Neutralization of Special Elements used in an OS Command ('OS Command…
60This week
CVE-2025-22398Dell Unity, version(s) 5.4 and prior, contain(s) an Improper Neutralization of Special Elements used in an OS Command ('OS Command…
40Plan
CVE-2022-29084Dell Unity, Dell UnityVSA, and Dell Unity XT versions before 5.2.0.0.5.173 do not restrict excessive authentication attempts in Unisphere…
40Plan

Published before and after this one in the same product

← EarlierCVE-2025-46422Oct 30, 2025 · Dell Unity, version(s) 5.5 and prior, contain(s) an Improper Neutralization of Special Elements used in an OS Command ('OS Command…
31Monitor
← EarlierCVE-2025-46423Oct 30, 2025 · Dell Unity, version(s) 5.5 and prior, contain(s) an Improper Neutralization of Special Elements used in an OS Command ('OS Command…
31Monitor
Later →CVE-2026-22277Jan 30, 2026 · Dell UnityVSA, version(s) 5.4 and prior, contain(s) an Improper Neutralization of Special Elements used in an OS Command ('OS Command…
31Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
Dell Unity	5.5.3	Vendor (CNA)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

CVE-2025-36604179 days apartDell Unity, version(s) 5.5 and prior, contain(s) an Improper Neutralization of Special Elements used in an OS Command ('OS Command…
60This week
CVE-2025-22398309 days apartDell Unity, version(s) 5.4 and prior, contain(s) an Improper Neutralization of Special Elements used in an OS Command ('OS Command…
40Plan
CVE-2024-49601309 days apartDell Unity, version(s) 5.4 and prior, contain(s) an Improper Neutralization of Special Elements used in an OS Command ('OS Command…
39Monitor
CVE-2025-24383309 days apartDell Unity, version(s) 5.4 and prior, contain(s) an Improper Neutralization of Special Elements used in an OS Command ('OS Command…
36Monitor
CVE-2026-222770 days apartDell UnityVSA, version(s) 5.4 and prior, contain(s) an Improper Neutralization of Special Elements used in an OS Command ('OS Command…
31Monitor
CVE-2025-4642292 days apartDell Unity, version(s) 5.5 and prior, contain(s) an Improper Neutralization of Special Elements used in an OS Command ('OS Command…
31Monitor

Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · public bounty program.

Technical details

Attack conditions

Someone with local access to the system can trigger it.
A low-privileged account is enough.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

Attack vector: Local
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-78 · Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

CVSS vector

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

nvd-secondary

Root cause

User input is inserted as text into a shell command. The shell may interpret special characters in the input as part of the command.

The bug in code

The whole CWE-78 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1const host = req.body.host;
2exec("ping -c 1 " + host, onResult);

Fixed

1const host = req.body.host;
2if (!/^[a-z0-9.-]{1,253}$/i.test(host)) return res.sendStatus(400);
3execFile("ping", ["-c", "1", host], onResult);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

—

Change log (1)

Fix✗ → ✓Sep 28, 2026, 10:11 PM UTC

For records you follow, these changes also arrive as notifications. →

References

www.dell.com/support/kbdoc/en-us/000421197/dsa-2026-054-security-update-for-dell-unity-dell-unityvsa-and-dell-unity-xt-security-update-for-multiple-vulnerabilities

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

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