Exploitation evidence
Known exploited · CISA KEV listed
Added 2023-06-23. Ransomware campaign use: Unknown.
CISA required action: Apply updates per vendor instructions.
CISA due date: 2023-07-14. This is the catalog’s deadline, not an assessment of your organization’s exposure.
KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗Reported products and versions
Zyxel / NAS326 firmware
Default status: unaffected
- affected: < V5.21(AAZF.14)C0
Zyxel / NAS540 firmware
Default status: unaffected
- affected: < V5.21(AATB.11)C0
Zyxel / NAS542 firmware
Default status: unaffected
- affected: < V5.21(ABAG.11)C0
Fixes and workarounds
No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.
Sources and related reporting
Observed change timeline
History begins when Egret first downloads each source. It is not the complete upstream CVE history.
12 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-12",
"epss": 0.82264,
"percentile": 0.99665
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.82264,
"percentile": 0.99663
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.82264,
"percentile": 0.99662
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.82264,
"percentile": 0.99662
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.82264,
"percentile": 0.99661
}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.82264,
"percentile": 0.99661
}06 Nov 2026, 06:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.82264,
"percentile": 0.9966
}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.82264,
"percentile": 0.9966
}04 Nov 2026, 18:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
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}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.82264,
"percentile": 0.99659
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.82264,
"percentile": 0.99659
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2023-27992",
"cwes": [
"CWE-78"
],
"dateAdded": "2023-06-23",
"dueDate": "2023-07-14",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Unknown",
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"product": "Multiple Network-Attached Storage (NAS) Devices",
"requiredAction": "Apply updates per vendor instructions.",
"shortDescription": "Multiple Zyxel network-attached storage (NAS) devices contain a pre-authentication command injection vulnerability that could allow an unauthenticated attacker to execute commands remotely via a crafted HTTP request.",
"vendorProject": "Zyxel",
"vulnerabilityName": "Zyxel Multiple NAS Devices Command Injection Vulnerability"
}