CVE-2026-7273
Zyxel — Zyxel GS1900 Series Switches Stack-Based Buffer Overflow Vulnerability
CISA KEV · in the CISA KEV catalog since 2026-09-21
What EVULNABLE says
Listed in the CISA KEV catalog, and an EPSS probability of 0.025.
Patch This Cycle
The priority band answers “how soon”, not “how bad” — see Methodology for what it weighs and where it abstains.
The evidence behind it
| Measure | Value | Source | What it means |
|---|---|---|---|
| CVSS base score | 8.8 | NVD | How severe the flaw is in itself. It does not say how likely an attack is. |
| FIRST EPSS | 0.025 (84.4th pctl) | FIRST | FIRST's estimate of the chance this is exploited in the next 30 days, and how that ranks against all CVEs. |
| Actively exploited | Confirmed | CISA KEV | Whether a source of record has confirmed attacks using it in the wild. |
| Ransomware campaign use | Unknown or none | CISA KEV | Whether CISA has seen ransomware operators use it. |
| CISA remediation deadline | 2026-09-24 — CISA federal deadline · Overdue by 23 days | CISA KEV | The date US federal agencies must have fixed or mitigated it. |
| Fixed in | gs1900-8 firmware: update to 2.90\(aahh.2\)c0 or later | gs1900-8hp firmware: update to 2.90\(aahi.2\)c0 or later | gs1900-10hp firmware: update to 2.90\(aazi.2\)c0 or later | gs1900-16 firmware: update to 2.90\(aahj.2\)c0 or later | gs1900-24 firmware: update to 2.90\(aahl.2\)c0 or later | gs1900-24e firmware: update to 2.90\(aahk.2\)c0 or later | NVD | The version(s) the vendor has published as fixed, where NVD records one. |
| Public exploit module | None known | Metasploit | Module existing is not the same as active exploitation. |
| EUVD cross-reference | Listed | ENISA EUVD | ENISA's own vulnerability database entry for this CVE, where one exists. |
Impacted software or hardware
- gs1900-8 firmware Operating system — < 2.90\(aahh.2\)c0
- gs1900-8hp firmware Operating system — < 2.90\(aahi.2\)c0
- gs1900-10hp firmware Operating system — < 2.90\(aazi.2\)c0
- gs1900-16 firmware Operating system — < 2.90\(aahj.2\)c0
- gs1900-24 firmware Operating system — < 2.90\(aahl.2\)c0
- gs1900-24e firmware Operating system — < 2.90\(aahk.2\)c0
- gs1900-24ep firmware Operating system — < 2.90\(abto.2\)c0
- gs1900-24hpv2 firmware Operating system — < 2.90\(abtp.2\)c0
+12 more affected products — see the full list at NVD.
Fixed versions: gs1900-8 firmware: update to 2.90\(aahh.2\)c0 or later | gs1900-8hp firmware: update to 2.90\(aahi.2\)c0 or later | gs1900-10hp firmware: update to 2.90\(aazi.2\)c0 or later | gs1900-16 firmware: update to 2.90\(aahj.2\)c0 or later | gs1900-24 firmware: update to 2.90\(aahl.2\)c0 or later | gs1900-24e firmware: update to 2.90\(aahk.2\)c0 or later
Remediation: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Remediation basis: CISA KEV required action
ENISA EUVD also lists this CVE at CVSS 8.8 (v3.1), assigned by Zyxel. Source: euvd.enisa.europa.eu.
22 days recorded, 2026-09-24 to 2026-10-15
2.50% as of 2026-10-15 (84.4th percentile). FIRST EPSS, recorded daily since this page started tracking it.
2026-09-24
2026-10-15
The primary records
This page is an opinion about urgency. Where it and a source of record disagree, the source of record is the record.
Where this sits
CVE-2026-7273 is one of the entries ranked on the priority feed and in the non-Microsoft advisories.