CVE-2017-7901
A Predictable Value Range from Previous Values issue was discovered in Rockwell Automation Allen-Bradley MicroLogix 1100…
- Published
- Updated
- Reserved
- Assigned by
- icscert
Description
A Predictable Value Range from Previous Values issue was discovered in Rockwell Automation Allen-Bradley MicroLogix 1100 programmable-logic controllers 1763-L16AWA, Series A and B, Version 16.00 and prior versions; 1763-L16BBB, Series A and B, Version 16.00 and prior versions; 1763-L16BWA, Series A and B, Version 16.00 and prior versions; and 1763-L16DWD, Series A and B, Version 16.00 and prior versions and Allen-Bradley MicroLogix 1400 programmable logic controllers 1766-L32AWA, Series A and B, Version 16.00 and prior versions; 1766-L32BWA, Series A and B, Version 16.00 and prior versions; 1766-L32BWAA, Series A and B, Version 16.00 and prior versions; 1766-L32BXB, Series A and B, Version 16.00 and prior versions; 1766-L32BXBA, Series A and B, Version 16.00 and prior versions; and 1766-L32AWAA, Series A and B, Version 16.00 and prior versions. Insufficiently random TCP initial sequence numbers are generated, which may allow an attacker to predict the numbers from previous values. This may allow an attacker to spoof or disrupt TCP connections, resulting in a denial of service for the target device.
Timeline
ID reserved
By icscert
- 2 months later
· 2 months later
Published
- 7 years later
· 7 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.0 | High8.6 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H |
- EPSS (exploitation in 30 days)
- 9.0% · top 4.7% of all CVEs (8 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.6.
Weakness
Affected products
Rockwell Automation Allen-Bradley MicroLogix 1100 and 1400
- affected Rockwell Automation Allen-Bradley MicroLogix 1100 and 1400
References (2)
- 1038546 (opens in a new tab)vdb-entryx_refsource_SECTRACKx_transferred
- https://ics-cert.us-cert.gov/advisories/ICSA-17-115-04 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2017-7901)Record last updated .