CVE-2026-4129: NI SystemLink · Missing Authorization
Affects NI SystemLinkSource CVE Database V5
Not known to be exploited · CVSS 8.1 High : upgrade to 26.5.0 soon.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 28% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-09-11.
- Patch
- Available – fixed in 26.5.0
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 10 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade SystemLink and SystemLink Server to 26.5.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| NISystemLink | Affected
| Fixed in
|
| NISystemLink Server | Affected
| Fixed in
|
Description
There is an improper access control vulnerability in NI SystemLink that may allow an authenticated user with limited privileges to access host operating system files and directories that should be restricted. This vulnerability affects NI SystemLink and NI SystemLink Server versions prior to 2026 Q3.