Exploitation evidence
Known exploited · CISA KEV listed
Added 2026-03-05. Ransomware campaign use: Unknown.
CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
CISA due date: 2026-03-26. 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
n/a / Rockwell Automation Studio 5000 Logix Designer, RSLogix 5000, Logix Controllers
Default status: Not specified
- affected: RSLogix 5000 Versions 16 through 20
- affected: Studio 5000 Logix Designer: Versions 21 and later
- affected: CompactLogix 1768, 1769, 5370, 5380, 5480
- affected: ControlLogix 5550, 5560, 5570, 5580
- affected: DriveLogix 5560, 5730, 1794-L34
- affected: Compact GuardLogix 5370, 5380
- affected: GuardLogix 5570, 5580
- affected: SoftLogix 5800
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": 0.6363,
"percentile": 0.99228
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.6363,
"percentile": 0.99223
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.6363,
"percentile": 0.99222
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.6363,
"percentile": 0.99221
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.6363,
"percentile": 0.99221
}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.6363,
"percentile": 0.9922
}06 Nov 2026, 06:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.6363,
"percentile": 0.99219
}06 Nov 2026, 00:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
{
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"content": {
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"timestamp": "2026-03-05T00:00:00+00:00",
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"cna": {
"affected": [
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"product": "Rockwell Automation Studio 5000 Logix Designer, RSLogix 5000, Logix Controllers",
"vendor": "n/a",
"versions": [
{
"status": "affected",
"version": "RSLogix 5000 Versions 16 through 20"
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{
"status": "affected",
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{
"status": "affected",
"version": "CompactLogix 1768, 1769, 5370, 5380, 5480"
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{
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"version": "ControlLogix 5550, 5560, 5570, 5580"
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{
"status": "affected",
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{
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"version": "Compact GuardLogix 5370, 5380"
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{
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"version": "GuardLogix 5570, 5580"
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"value": "Rockwell Automation Studio 5000 Logix Designer Versions 21 and later, and RSLogix 5000 Versions 16 through 20 use a key to verify Logix controllers are communicating with Rockwell Automation CompactLogix 1768, 1769, 5370, 5380, 5480: ControlLogix 5550, 5560, 5570, 5580; DriveLogix 5560, 5730, 1794-L34; Compact GuardLogix 5370, 5380; GuardLogix 5570, 5580; SoftLogix 5800. Rockwell Automation Studio 5000 Logix Designer Versions 21 and later and RSLogix 5000: Versions 16 through 20 are vulnerable because an unauthenticated attacker could bypass this verification mechanism and authenticate with Rockwell Automation CompactLogix 1768, 1769, 5370, 5380, 5480: ControlLogix 5550, 5560, 5570, 5580; DriveLogix 5560, 5730, 1794-L34; Compact GuardLogix 5370, 5380; GuardLogix 5570, 5580; SoftLogix 5800."
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"dateUpdated": "2021-03-03T17:59:43.000Z",
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{
"version_value": "DriveLogix 5560, 5730, 1794-L34"
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{
"version_value": "Compact GuardLogix 5370, 5380"
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{
"version_value": "GuardLogix 5570, 5580"
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{
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"value": "Rockwell Automation Studio 5000 Logix Designer Versions 21 and later, and RSLogix 5000 Versions 16 through 20 use a key to verify Logix controllers are communicating with Rockwell Automation CompactLogix 1768, 1769, 5370, 5380, 5480: ControlLogix 5550, 5560, 5570, 5580; DriveLogix 5560, 5730, 1794-L34; Compact GuardLogix 5370, 5380; GuardLogix 5570, 5580; SoftLogix 5800. Rockwell Automation Studio 5000 Logix Designer Versions 21 and later and RSLogix 5000: Versions 16 through 20 are vulnerable because an unauthenticated attacker could bypass this verification mechanism and authenticate with Rockwell Automation CompactLogix 1768, 1769, 5370, 5380, 5480: ControlLogix 5550, 5560, 5570, 5580; DriveLogix 5560, 5730, 1794-L34; Compact GuardLogix 5370, 5380; GuardLogix 5570, 5580; SoftLogix 5800."
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"datePublished": "2021-03-03T17:59:43.000Z",
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}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.6363,
"percentile": 0.99218
}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.6363,
"percentile": 0.99217
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.6363,
"percentile": 0.99216
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2021-22681",
"cwes": [
"CWE-522"
],
"dateAdded": "2026-03-05",
"dueDate": "2026-03-26",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Unknown",
"notes": "https://support.rockwellautomation.com/app/answers/answer_view/a_id/1130301/~/cve-2021-22681%3A-authentication-bypass-vulnerability-found-in-logix-controllers- ; https://www.cisa.gov/news-events/ics-advisories/icsa-21-056-03 ; https://nvd.nist.gov/vuln/detail/CVE-2021-22681",
"product": "Multiple Products",
"requiredAction": "Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.",
"shortDescription": "Multiple Rockwell products contain an insufficient protected credentials vulnerability. Studio 5000 Logix Designer software may allow a key to be discovered. This key is used to verify Logix controllers are communicating with Rockwell Automation design software. If successfully exploited, this vulnerability could allow an unauthorized application to connect with Logix controllers. To leverage this vulnerability, an unauthorized user would require network access to the controller.",
"vendorProject": "Rockwell",
"vulnerabilityName": "Rockwell Multiple Products Insufficient Protected Credentials Vulnerability"
}