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CVE-2019-12583· NVD / CVE Program· CNA mitre

Missing Access Control in the "Free Time" component of several Zyxel UAG, USG, and ZyWall devices allows a remote attacker to generate guest

Noroxi assessment

Priority: Plan (action score 49/100)

  • A ready-made attack module is public (Nuclei); exploiting it takes no special expertise.
  • Probability of exploitation in the next 30 days: 43.9% (FIRST EPSS); higher than 98.7% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to the record, no fixed version is available yet.

Add it to your regular patch cycle. Update when a fix is released; follow the vendor's advisory.

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

Missing Access Control in the "Free Time" component of several Zyxel UAG, USG, and ZyWall devices allows a remote attacker to generate guest accounts by directly accessing the account generator. This can lead to unauthorised network access or Denial of Service.

CriticalCVSS 9.1 · v3.0—Proof of concept No fix recorded
Published
Jun 27, 2019
Updated
Jun 16, 2026
EPSS
43.9% · 98th percentile

Report tools

JSON

Action score

49

Plan

Add it to your regular patch cycle.

CVSS
36 / 40 · 9.1 / 10
CISA KEV
0 / 30 · Not listed
EPSS
13 / 30 · 43.9%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • Proof of concept exists, no weaponized module
  • No fixed version yet

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

Follow CVE-2019-12583

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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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.

VendorProduct
zyxeluag2100 firmware
zyxeluag2100
zyxeluag4100 firmware
zyxeluag4100
zyxeluag5100 firmware
zyxeluag5100
zyxelusg110 firmware
zyxelusg110
zyxelusg210 firmware
zyxelusg210
zyxelusg310 firmware
zyxelusg310

and 16 more

Affected versions

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

  • zyxel uag2100 firmwareup to 4.18\(aaiz.1\)c0 inclusive
  • zyxel uag4100 firmwareup to 4.18\(aatd.1\)c0 inclusive
  • zyxel uag5100 firmwareup to 4.18\(aapn.1\)c0 inclusive
  • zyxel usg110 firmwareup to 4.33\(aaph.0\)c0 inclusive
  • zyxel usg1100 firmwareup to 4.33\(aapk.0\)c0 inclusive
  • zyxel usg1900 firmwareup to 4.33\(aapl.0\)c0 inclusive
  • zyxel usg210 firmwareup to 4.33\(aapi.0\)c0 inclusive
  • zyxel usg2200-vpn firmwareup to 4.33\(abae.0\)c0 inclusive
  • zyxel usg310 firmwareup to 4.33\(aapj.0\)c0 inclusive
  • zyxel zywall 110 firmwareup to 4.33\(aaaa.0\)c0 inclusive
  • zyxel zywall 1100 firmwareup to 4.33\(aaac.0\)c0 inclusive
  • zyxel zywall 310 firmwareup to 4.33\(aaab.0\)c0 inclusive
  • zyxel zywall vpn100 firmwareup to 10.02\(abfv.0\)c0 inclusive
  • zyxel zywall vpn300 firmwareup to 10.02\(abfc.0\)c0 inclusive

Same product

zyxel: all records

Other highest-scoring records for the same primary product.

  • CVE-2019-12581A reflective Cross-site scripting (XSS) vulnerability in the free_time_failed.cgi CGI program in selected Zyxel ZyWall, USG, and UAG devices
    26Monitor

Remediation

Which version to upgrade to

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

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

Proof of concept available

A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.

Evidence

  • Nuclei detection template ×1

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
SourceKindDate
Nuclei detection templateNuclei template CVE-2019-12583 —

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.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

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

  • Anyone who can reach it over the internet 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
none
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-425 · Direct Request ('Forced Browsing')

CVSS vector

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

nvd-primary

Attack context

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

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

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

All records