CVE-2017-6884
A command injection vulnerability was discovered on the Zyxel EMG2926 home router with firmware V1.00(AAQT.4)b8. The vulnerability is located in the diagnostic tools, specifically the nslookup function. A malicious user may exploit numerous vectors to execute arbitrary commands on the router, such as the ping_ip parameter to the expert/maintenance/diagnostic/nslookup URI.
- CVSS
- 8.8Highscored by CISA
- Exploited in the wild
- Yes, in CISA KEV since 18 Sept 2023CISA deadline for US federal agencies: 9 Oct 2023known use in ransomware campaignspublic exploit code
- EPSS
- 33.0%chance of exploitation in the next 30 daystop 2% of scored CVEsFIRST score of 11 Nov 2026
- Fix
- Not stated by the vendorno fixed release in the CVE record
- Published
- 6 Apr 2017analysed here 12 Nov 2026
Do first. Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. (CISA's required action for this KEV entry)
Summary
Triage
The summary, impact and action text on this page are written by our AI analysis pipeline, or taken from the NVD description when a CVE was imported from NVD. They are not the vendor's wording: check them against the sources. A longer AI executive summary and technical analysis are generated for signed-in accounts on the Max plan.
Affected products
Products named in our analysis
- zyxel:emg2926_firmware
Fix and mitigation
WAF and other mitigations
Can a WAF block it? Partly. OS command injection puts shell syntax into the request. WAF rules catch common shell commands but miss encoded or unusual payloads.
Also consider: shlex/execve-style APIs
Based on the weakness type only; no CVE-specific evidence yet. We check Cloudflare, AWS, Google Cloud Armor and Azure; for Akamai, Imperva, Fastly, F5, ask your vendor.
Remediation steps (AI-written)
Step-by-step remediation is generated for accounts on the Max plan, for CVEs that match a technology in their stack. Add this technology to your stack to see the fix checklist.
Exploitation evidence
- CISA KEV catalog
- Listed since 18 Sept 2023. Known use in ransomware campaigns.
- CISA due date
- 9 Oct 2023, the remediation deadline for US federal agencies
- CISA required action
- Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- Public exploit code
- Yes: 1 on Exploit-DB
- CISA SSVC
- exploitation active, automatable no, technical impact totalAssessed by CISA 4 Aug 2026 (SSVC 2.0.3). Exploitation is none, poc (public proof of concept) or active.
Exploit-DB
- Zyxel_ EMG2926 < V1.00(AAQT.4)b8 - OS Command Injectionwebapps, 2 Apr 2017
Listed so you can judge urgency, not as a recommendation to run anything. GitHub “proofs of concept” are unvetted: some are fake or carry malware. Exploit-DB marks the entries its staff verified.
Timeline
- 2 Apr 2017First public exploit or proof of concept
- 6 Apr 2017Published5 days later
- 18 Sept 2023Added to CISA KEV (exploited in the wild)2,355 days (about 6 years) later
- 9 Oct 2023CISA remediation due date (US federal agencies)21 days later
- 4 Aug 2026CISA SSVC assessment: exploitation active1,030 days (about 3 years) later
- 1 Oct 2026CVE record last updated59 days later
- 12 Nov 2026Analysed by vulneraibility.com42 days later
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
| Metric | Value | What it means |
|---|---|---|
| Attack vector | NetworkReachable over the internet or any routable network. | Reachable over the internet or any routable network. |
| Attack complexity | LowRepeatable attack, no special conditions. | Repeatable attack, no special conditions. |
| Privileges required | LowThe attacker needs basic user privileges. | The attacker needs basic user privileges. |
| User interaction | NoneNo victim action needed. | No victim action needed. |
| Scope | UnchangedImpact stays within the vulnerable component. | Impact stays within the vulnerable component. |
| Confidentiality | HighTotal data disclosure possible. | Total data disclosure possible. |
| Integrity | HighComplete modification possible. | Complete modification possible. |
| Availability | HighFull outage possible. | Full outage possible. |
Common questions
Is CVE-2017-6884 being exploited?
Yes. CVE-2017-6884 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.
How severe is CVE-2017-6884?
CVE-2017-6884 is rated High with a CVSS score of 8.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2017-6884?
Not known from our data. No patch reference has been recorded for CVE-2017-6884, which is not the same as no patch existing — a fix may have shipped without a tagged reference, or after this record was written. The vendor advisory is the only authority on whether a fix exists, and mitigations may be available regardless.
What does CVE-2017-6884 affect?
CVE-2017-6884 affects zyxel:emg2926_firmware. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
References
2 references in the CVE record, grouped by the tags the record gives them.
Exploits (1)
- exploit-db.com /exploits/41782/
Other links (1)
- cisa.gov /known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-6884
Where the data on this page comes from
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- CISA KEV catalog: exploitation, date added, due date
- CISA Vulnrichment (ADP): SSVC decision points
- FIRST EPSS: exploit probability and percentile
- Exploit-DB: published exploits
Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.
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