Exploitation evidence
Known exploited · CISA KEV listed
Added 2024-01-17. Ransomware campaign use: Unknown.
CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
CISA due date: 2024-02-07. 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
Cloud Software Group / NetScaler ADC
Default status: unaffected
- affected: 14.1 to < 12.35 (patch)
- affected: 13.1 to < 51.15 (patch)
- affected: 13.0 to < 92.21 (patch)
- affected: 13.1-FIPS to < 37.176 (patch)
- affected: 12.1-FIPS to < 55.302 (patch)
- affected: 12.1-NDcPP to < 55.302 (patch)
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": 0.57633,
"percentile": 0.99094
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.57633,
"percentile": 0.99089
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.57633,
"percentile": 0.99088
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.57633,
"percentile": 0.99087
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.57633,
"percentile": 0.99087
}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.57633,
"percentile": 0.99087
}06 Nov 2026, 06:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.57633,
"percentile": 0.99086
}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.57633,
"percentile": 0.99085
}04 Nov 2026, 18:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
{
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"title": "CISA ADP Vulnrichment"
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"cna": {
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"datePublished": "2024-01-17T20:15:53.345Z",
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}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.57633,
"percentile": 0.99084
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.57633,
"percentile": 0.99083
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2023-6549",
"cwes": [
"CWE-119"
],
"dateAdded": "2024-01-17",
"dueDate": "2024-02-07",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Unknown",
"notes": "https://support.citrix.com/article/CTX584986/netscaler-adc-and-netscaler-gateway-security-bulletin-for-cve20236548-and-cve20236549; https://nvd.nist.gov/vuln/detail/CVE-2023-6549",
"product": "NetScaler ADC and NetScaler Gateway",
"requiredAction": "Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.",
"shortDescription": "Citrix NetScaler ADC and NetScaler Gateway contain a buffer overflow vulnerability that allows for a denial-of-service when configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) or AAA virtual server.",
"vendorProject": "Citrix",
"vulnerabilityName": "Citrix NetScaler ADC and NetScaler Gateway Buffer Overflow Vulnerability"
}