CVE Intelligence
High

CVE-2026-8047 — Out-of-bounds Write in CODESYS Control

The affected products perform improper length checking when parsing incoming HTTP requests, resulting in a size-limited out-of-bounds write. An unauthenticated remote attacker can exploit this flaw to cause a denial of service via a system crash on the affected device.

Published May 26, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: CERTVDE

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.6% (30-day exploitation probability)+7
  • Technical severity (high)+6
  • Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.57%
ahead of 46% of scored CVEs · Oct 14, 2026
Affects
CODESYS
CODESYS Control RTE (for Beckhoff CX) SL and 15 more
CVSS base
7.5
High · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
Yes
can an attacker script the kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (CODESYS CODESYS Control RTE (for Beckhoff CX) SL, CODESYS Control For Beaglebone Sl, CODESYS Control For Empc-a/imx6 Sl…).
  2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  4. Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
CODESYS CODESYS Control RTE (for Beckhoff CX) SL ≥ 3.5.21.0 and < 3.5.22.20 Vulnerable CVE Program (cve.org) e CISA ADP
CODESYS Control For Beaglebone Sl ≥ 4.15.0.0 and < 4.21.0.0 Vulnerable CVE Program (cve.org) e CISA ADP
CODESYS Control For Empc-a/imx6 Sl ≥ 4.15.0.0 and < 4.21.0.0 Vulnerable CVE Program (cve.org) e CISA ADP
CODESYS Control For Iot2000 Sl ≥ 4.15.0.0 and < 4.21.0.0 Vulnerable CVE Program (cve.org) e CISA ADP
CODESYS Control For Linux Arm Sl ≥ 4.15.0.0 and < 4.21.0.0 Vulnerable CVE Program (cve.org) e CISA ADP
CODESYS Control For Linux Sl ≥ 4.15.0.0 and < 4.21.0.0 Vulnerable CVE Program (cve.org) e CISA ADP
CODESYS Control For Pfc100 Sl ≥ 4.15.0.0 and < 4.21.0.0 Vulnerable CVE Program (cve.org) e CISA ADP
CODESYS Control For Pfc200 Sl ≥ 4.15.0.0 and < 4.21.0.0 Vulnerable CVE Program (cve.org) e CISA ADP
CODESYS Control For Plcnext Sl ≥ 4.15.0.0 and < 4.21.0.0 Vulnerable CVE Program (cve.org) e CISA ADP
CODESYS Control For Raspberry Pi Sl ≥ 4.15.0.0 and < 4.21.0.0 Vulnerable CVE Program (cve.org) e CISA ADP
CODESYS Control For Wago Touch Panels 600 Sl ≥ 0.0.0 and < 4.21.0.0 Vulnerable CVE Program (cve.org) e CISA ADP
CODESYS Control Rte Sl ≥ 3.5.21.0 and < 3.5.22.20 Vulnerable CVE Program (cve.org) e CISA ADP
CODESYS Control Win Sl ≥ 3.5.21.0 and < 3.5.22.20 Vulnerable CVE Program (cve.org) e CISA ADP
CODESYS Hmi Sl ≥ 3.5.21.0 and < 3.5.22.20 Vulnerable CVE Program (cve.org) e CISA ADP
CODESYS Runtime Toolkit ≥ 3.5.21.0 and < 3.5.22.20 Vulnerable CVE Program (cve.org) e CISA ADP
CODESYS Virtual Control Sl ≥ 4.15.0.0 and < 4.21.0.0 Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
8.7 CVSS 4.0 High — — info@cert.vde.com via NIST National Vulnerability Database
8.7 CVSS 4.0 High — — CERTVDE via CVE Program (cve.org) e CISA ADP
7.5 CVSS 3.1 High 3.9 3.6 info@cert.vde.com via NIST National Vulnerability Database
7.5 CVSS 3.1 High — — CERTVDE via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (score shown at the top: info@cert.vde.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-1284

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.57%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · codesys/codesys control rte (sl), codesys/codesys control rte (for beckhoff cx) sl, codesys/codesys control win (sl), co
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • CVSS changed · 7.5
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Awaiting Analysis
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVE published
    May 26, 2026 · CERTVDE

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

1 on the record

Elsewhere on this site

CODESYS
every CVE for this vendor
CWE-1284
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-8046 Incorrect Authorization in CODESYS Control May 26, 2026
  • CVE-2026-3509 CODESYS Control Audit Log Format String DoS Mar 24, 2026
  • CVE-2025-41660 CODESYS Control Boot Application Replacement Enables Code Execution Mar 24, 2026
  • CVE-2025-41738 CODESYS Control - Invalid type usage in visualization Dec 1, 2025
  • CVE-2025-41739 CODESYS Control - Linux/QNX SysSocket flaw Dec 1, 2025

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No fixed version, patch or mitigation documented.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-8047 is "Out-of-bounds Write in CODESYS Control", rated High. It affects CODESYS Control RTE (for Beckhoff CX) SL (CODESYS); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.5 describes technical severity. EPSS 0.57% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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