CVE & CISA-KEV Catalog

CVE-2021-33485

CRITICAL
9.8
CVSS v3
NVD

Description

CODESYS Control Runtime system before 3.5.17.10 has a Heap-based Buffer Overflow.

CWE-787Out-of-bounds WriteCWE-122Heap-based Buffer Overflow

How to fix

Remediation Available
controlNVD
Affected:< 4.2.0.0Fixed in:4.2.0.0CVE-2021-33485derived from NVD
control rteNVD
Affected:< 3.5.17.10Fixed in:3.5.17.10CVE-2021-33485derived from NVD
control runtime system toolkitNVD
Affected:< 3.5.17.10Fixed in:3.5.17.10CVE-2021-33485derived from NVD
control win slNVD
Affected:< 3.5.17.10Fixed in:3.5.17.10CVE-2021-33485derived from NVD
embedded target visu toolkitNVD
Affected:< 3.5.17.10Fixed in:3.5.17.10CVE-2021-33485derived from NVD
hmiNVD
Affected:< 3.5.17.10Fixed in:3.5.17.10CVE-2021-33485derived from NVD
remote target visu toolkitNVD
Affected:< 3.5.17.10Fixed in:3.5.17.10CVE-2021-33485derived from NVD

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged

Impact

ConfidentialityHigh
IntegrityHigh
AvailabilityHigh

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

Exploit Intelligence

1.14%probability of exploitation in 30 days
63rdpercentile

Moderate risk: more likely to be exploited than 63% of all known CVEs.

References

Vendor Advisory1

Related Vulnerabilities

Other CWE-787 (Out-of-bounds Write) vulnerabilities, ordered by exploit likelihood. View all

CVESeverityCVSSEPSSExploitedFix
CVE-2025-22457Critical9.0100%KEV + RansomFix
CVE-2025-0282Critical9.0100%KEV + Ransom-
CVE-2015-3113Critical9.8100%KEVFix
CVE-2021-20038Critical9.8100%KEV + Ransom-
CVE-2023-4863High8.8100%KEVFix
CVE-2020-16040Medium6.5100%-Fix
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CVE-2021-33485 severity badge

Markdown

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HTML

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-05-29.