CVE-2026-9625
CVE-2026-9625 — RSLinx Classic® - Multiple Vulnerabilities
A denial-of-service security issue exists within RSLinx® Classic. A crafted CIP packet with an oversized embedded message request can cause the RSLinx® Classic service to crash, requiring a restart of the service to recover.
Published Updated Sources: NVD, Rockwell Automation (CNA), SOCRadar CTI
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Unreported
no source claims exploitation
EPSS
0%
ahead of 0% of scored CVEs
CVSS base
8.7
high
Remediation
The vendor's own words where we have them.
Upgrade RSLinx Classic® to a fixed release. Apply vendor patches per advisory and restrict external exposure of the affected component until patched.
First 24 hours
Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.
- Identify exposed assets running affected vendor/product/version combinations.
- Prioritize based on EPSS, PoC availability, and external exposure.
- Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.
Affected scope
Vendor, product and version as the advisories word them.
| Vendor | Product | Versions | Status |
|---|---|---|---|
| Rockwell Automation | RSLinx Classic® | V4.50 and prior | Vulnerable |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Attack Complexity
Low
Attack Vector
Network
Privileges Req
None
User Interaction
None
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 8.7 | CVSS 4.0 | high | — | — | Rockwell Automation (CNA) |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
What this weakness leads to
MITRE's own consequences and mitigations for the weakness class — the authority's wording, not guidance derived from the CVSS vector.
CWE-120 · Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
- Modify Memory
- Execute Unauthorized Code or Commands
- DoS: Crash, Exit, or Restart
- DoS: Resource Consumption (CPU)
Mitigation: Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
Weakness & attack patterns
- CWE-120Classic Buffer Overflow
Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.
Detection
Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.
- Prioritize edge telemetry for network-reachable RSLinx Classic®.
Timeline
What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.
- 2026
Added · CVSS 3.1 8.7 (AV:N)
Sep 1, 2026 · NVD
Initial · CVE published
Sep 1, 2026 · NVD
CVE published by MITRE.
Sep 1, 2026 · SOCRadar CTI
References
1 on the record
Elsewhere on this site
- Rockwell Automationevery CVE for this vendor
- Memory Corruptionsame class
- CWE-120other pages naming this weakness
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 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 record1
What should defenders know first?
CVE-2026-9625 is RSLinx Classic® - Multiple Vulnerabilities, a high vulnerability affecting RSLinx Classic® from Rockwell Automation. The current evidence does not list it in CISA KEV, and the exploit status is: Active exploitation is not confirmed from current sources for CVE-2026-9625. Public exploit evidence is: A public PoC is not confirmed from current sources for CVE-2026-9625. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS 8.7 describes technical severity, while EPSS 0% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.