NVD / CVE Program· CNA hackerone

CVE-2026-21639: A malicious actor in Wi-Fi range of the affected product could leverage a vulnerability in the airMAX Wireless Protocol to achieve a remote

Noroxi assessment

Priority: Monitor (action score 35/100)

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: 0.39% (FIRST EPSS).
Someone on the same network segment can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
Fixed version: Ubiquiti Inc airFiber AF60 2.6.8; Ubiquiti Inc airFiber AF60-XG 1.2.3; Ubiquiti Inc airMAX AC 8.7.21.

Low priority for now. Upgrade to Ubiquiti Inc airFiber AF60 2.6.8; Ubiquiti Inc airFiber AF60-XG 1.2.3; Ubiquiti Inc airMAX AC 8.7.21 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

A malicious actor in Wi-Fi range of the affected product could leverage a vulnerability in the airMAX Wireless Protocol to achieve a remote code execution (RCE) within the affected product.

HighCVSS 8.8 · v3.1—No exploit Fix available

Published: Jan 8, 2026
Updated: Jul 30, 2026
EPSS: 0.3% · 33th percentile
CWE: CWE-120

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 35 / 40 · 8.8 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.3%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: —
CNA · hackerone: 8.8; 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

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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
ui	airmax ac firmware	cpe:2.3:o:ui:airmax_ac_firmware
ui	airmax ac	cpe:2.3:h:ui:airmax_ac
ui	airmax m firmware	cpe:2.3:o:ui:airmax_m_firmware
ui	airmax m	cpe:2.3:h:ui:airmax_m
ui	airfiber af60-xg firmware	cpe:2.3:o:ui:airfiber_af60-xg_firmware
ui	airfiber af60-xg	cpe:2.3:h:ui:airfiber_af60-xg
ui	airfiber af60 firmware	cpe:2.3:o:ui:airfiber_af60_firmware
ui	airfiber af60	cpe:2.3:h:ui:airfiber_af60

Affected versions

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

ui airfiber af60 firmwarebefore 2.6.8
ui airfiber af60-xg firmwarebefore 1.2.3
ui airmax ac firmwarebefore 8.7.21
ui airmax m firmwarebefore 6.3.24

Versions reported by the vendor

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

Ubiquiti Inc airFiber AF60
- before 2.6.8affected · semver
Ubiquiti Inc airFiber AF60-XG
- before 1.2.3affected · semver
Ubiquiti Inc airMAX AC
- before 8.7.21affected · semver
Ubiquiti Inc airMAX M
- before 6.3.24affected · semver

Same product

ui: all records

Other highest-scoring records for the same primary product.

CVE-2015-9266Ubiquiti airOS HTTP(S) unauthenticated arbitrary file upload
61This week

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
Ubiquiti Inc airFiber AF60	2.6.8	Vendor (CNA)
Ubiquiti Inc airFiber AF60-XG	1.2.3	Vendor (CNA)
Ubiquiti Inc airMAX AC	8.7.21	Vendor (CNA)
Ubiquiti Inc airMAX M	6.3.24	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.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

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

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Someone on the same network segment can trigger it.
No account or password is required.
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: Adjacent
Attack complexity: Low
Privileges required: None
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-120 · Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

CVSS vector

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

nvd-secondary

Root cause

When data is copied, the source length is not compared with the size of the destination buffer. Excess data overwrites adjacent memory.

The bug in code

The whole CWE-120 class

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

Vulnerable

1char buf[256];
2memcpy(buf, pkt->data, pkt->len);

Fixed

1char buf[256];
2if (pkt->len > sizeof(buf)) {
3  return -EINVAL;
4}
5memcpy(buf, pkt->data, pkt->len);

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

Fix✗ → ✓Sep 28, 2026, 10:11 PM UTC

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

References

community.ui.com/releases/Security-Advisory-Bulletin-061-061/1e4fe5f8-29c7-4a7d-a518-01b1537983ba

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

All records