CVE-2021-33485
CVE-2021-33485 is a critical-severity vulnerability in Codesys Control with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 7.5
- EPSS exploit prediction: 1% (63rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Codesys Control
- Published:
- Last modified:
Description
CODESYS Control Runtime system before 3.5.17.10 has a Heap-based Buffer Overflow.
Frequently asked questions
- What is CVE-2021-33485?
- CODESYS Control Runtime system before 3.5.17.10 has a Heap-based Buffer Overflow.
- How severe is CVE-2021-33485?
- CVE-2021-33485 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-33485 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-33485?
- CVE-2021-33485 primarily affects Codesys Control. In total, 16 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-33485?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2021-33485 published?
- CVE-2021-33485 was published on 2021-08-03 and last updated on 2026-06-17.
References
Affected products (16)
- cpe:2.3:a:codesys:control:*:*:*:*:*:beaglebone_sl:*:*
- cpe:2.3:a:codesys:control:*:*:*:*:*:empc-a\/imx6_sl:*:*
- cpe:2.3:a:codesys:control:*:*:*:*:*:iot2000_sl:*:*
- cpe:2.3:a:codesys:control:*:*:*:*:*:linux_sl:*:*
- cpe:2.3:a:codesys:control:*:*:*:*:*:pfc100_sl:*:*
- cpe:2.3:a:codesys:control:*:*:*:*:*:pfc200_sl:*:*
- cpe:2.3:a:codesys:control:*:*:*:*:*:plcnext_sl:*:*
- cpe:2.3:a:codesys:control:*:*:*:*:*:raspberry_pi_sl:*:*
- cpe:2.3:a:codesys:control:*:*:*:*:*:wago_touch_panels_600_sl:*:*
- cpe:2.3:a:codesys:control_rte:*:*:*:*:*:-:*:*
- cpe:2.3:a:codesys:control_rte:*:*:*:*:*:beckhoff_cx:*:*
- cpe:2.3:a:codesys:control_runtime_system_toolkit:*:*:*:*:*:*:*:*
- cpe:2.3:a:codesys:control_win_sl:*:*:*:*:*:*:*:*
- cpe:2.3:a:codesys:embedded_target_visu_toolkit:*:*:*:*:*:*:*:*
- cpe:2.3:a:codesys:hmi:*:*:*:*:*:*:*:*
- cpe:2.3:a:codesys:remote_target_visu_toolkit:*:*:*:*:*:*:*:*
More vulnerabilities in Codesys Control
- CVE-2021-36763 — High (CVSS 7.5): In CODESYS V3 web server before 3.5.17.10, files or directories are accessible to External Parties.
All CVEs affecting Codesys Control →
Other CWE-787 (Out-of-bounds Write) vulnerabilities
- CVE-2026-42369 — Critical (CVSS 10.0): GV-VMS V20 is a Video Monitoring Software used to gather the feeds of many surveillance cameras and manage other…
- CVE-2026-4746 — Critical (CVSS 10.0): Out-of-bounds Write vulnerability in timeplus-io proton (base/poco/Foundation/src modules). This vulnerability is…
- CVE-2025-43300 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 15.8.5 and iPadOS…
- CVE-2025-24201 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved checks to prevent unauthorized actions. This issue is fixed in…
- CVE-2024-42479 — Critical (CVSS 10.0): llama.cpp provides LLM inference in C/C++. The unsafe `data` pointer member in the `rpc_tensor` structure can cause…
- CVE-2024-39791 — Critical (CVSS 10.0): Stack-based buffer overflow vulnerabilities affecting Vonets industrial wifi bridge relays and wifi bridge…