CVE-2026-7273
Published Jun 16, 2026
Last updated a month ago
- Description
- A stack-based buffer overflow vulnerability in the CGI program of Zyxel GS1900-48HPv2 firmware versions through 2.90(ABTQ.1)C0 could allow a LAN-based, unauthenticated attacker to exploit the flaw and potentially execute OS commands via a crafted HTTP request.
- Source
- security@zyxel.com.tw
- NVD status
- Analyzed
- Products
- gs1900-8_firmware, gs1900-8hp_firmware, gs1900-10hp_firmware, gs1900-16_firmware, gs1900-24_firmware, gs1900-24e_firmware, gs1900-24ep_firmware, gs1900-24hpv2_firmware, gs1900-48_firmware, gs1900-48hpv2_firmware
CVSS 3.1
- Type
- Secondary
- Base score
- 8.8
- Impact score
- 5.9
- Exploitability score
- 2.8
- Vector string
- CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Severity
- HIGH
Data from CISA
- Vulnerability name
- Zyxel GS1900 Series Switches Stack-Based Buffer Overflow Vulnerability
- Exploit added on
- Sep 21, 2026
- Exploit action due
- Sep 24, 2026
- Required action
- 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.
- security@zyxel.com.tw
- CWE-121
- Hype score
- Not currently trending
🚨 CRITICAL: CVE-2026-7273 - Zyxel GS1900 switches vulnerable to stack-based buffer overflow. Unauthenticated LAN attackers can execute OS commands via crafted HTTP requests. Patch immediately. CISA KEV listed. #CVE #PatchNow https://t.co/uNjc3TlUFD
@DFIR_Lab
4 Oct 2026
34 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
🚨 #ALERT — ZYXEL GS1900 COMMAND EXECUTION FLAW ACTIVELY EXPLOITED September 21, 2026 DISCLOSED BY: Zyxel CONFIRMED EXPLOITED BY: CISA PRODUCT: Zyxel GS1900 Series Smart Managed Switches CVE: CVE-2026-7273 AFFECTED VERSIONS: Affected GS1900 models running firmware
@Python_s_
28 Sept 2026
41 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
🚨 #ALERT — ACTIVELY EXPLOITED ZYXEL GS1900 FLAW DATE: September 21, 2026 CONFIRMED BY: CISA KEV / GreyNoise VENDOR: Zyxel PRODUCT: #Zyxel GS1900 Series Switches CVE: CVE-2026-7273 IMPACT: A LAN-based unauthenticated attacker can exploit a stack-based buffer overflow in t
@Python_s_
23 Sept 2026
51 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
1/4 Timeline, not rumor. Exploit landed before the catalog stamp. Sep 12 — Check Point Management exploitation in the wild (vendor) Sep 17 — Zyxel GS1900 CVE-2026-7273 exploitation observed Sep 21 — CISA KEV: CVE-2026-7273. Federal due Thu Sep 24 Sep 22 — CISA KEV four-pa
@seoscottsdale
23 Sept 2026
187 Impressions
3 Retweets
2 Likes
1 Bookmark
4 Replies
0 Quotes
Patch Now | September 23, 2026 Bringing these vulnerabilities to your attention: - Zyxel GS1900 switches (CVE-2026-7273) - Check Point Security Management (CVE-2026-93616, CVSS 9.8) - Veeam Agent for Windows (CVE-2026-32996) https://t.co/fR71dyoG2H | #CyberSafeUG #CERTUGCC htt
@CERT_UG
23 Sept 2026
72 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
🔴 Zyxel GS1900 under aktiv attack! ⚠️ CVE-2026-7273 (CVSS 8,8) uppges utnyttjas aktivt. Sårbarheten kan möjliggöra kommandokörning utan inloggning. 🛡️ Begränsa åtkomst och uppdatera firmware! https://t.co/KQbAoEH5zh #Zyxel #CyberSecurity #CVE
@LabOpsIT
23 Sept 2026
2 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
【緊急】Zyxel GS1900スイッチに深刻な脆弱性（CVE-2026-7273 / CVSS 8.8） 修正版は6月16日に出ています。当てていない機器が48か国996台で侵入済みです。 対処: 管理画面で機種とファーム版を確認し、修正版へ更新。
@ForsmileDNet
23 Sept 2026
1 Impression
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
CISA added actively-exploited Zyxel GS1900 switch flaw CVE-2026-7273 to its KEV catalog — ~1,000 devices compromised across 48 countries. A separate Veeam Agent privesc bug (CVE-2026-32996) is also under attack. Patch now. #Zyxel #CISA #Veeam https://t.co/b5ctMmJ99J
@DEVOTOMSOLUTION
22 Sept 2026
5 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
Attacker compromised nearly 1000 Zyxel switches since August (CVE-2026-7273): A Chinese-speaking threat actor has exploited a vulnerability (CVE-2026-7273) in unpatched ZyXEL GS1900 Smart Managed Switches and has exfiltrated sensitive data from 996… https://t.co/fFSMrMeH54 http
@shah_sheikh
22 Sept 2026
38 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
Active attacks target Zyxel GS1900 switches (CVE-2026-7273) and Veeam Agent for Windows (CVE-2026-32996), enabling command and SYSTEM access. Patch now. #Cybersecurity #Vulnerability #ThreatIntel https://t.co/GFsXT6jw36
@CyberWorldOps
22 Sept 2026
32 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
CISA added Zyxel GS1900 CVE-2026-7273 to KEV after confirmed exploitation. Unauth LAN attackers can run OS commands. Arctic Wolf reports Veeam Agent CVE-2026-32996 abused to SYSTEM. The Hacker News, Sep 22. Verify independently. #CyberSecurity #InfoSec #Threatalis #CVE https://t.
@ThreatAlis
22 Sept 2026
3 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
Zyxel GS1900 switches (CVE-2026-7273) and Veeam Agent for Windows (CVE-2026-32996) are under active exploitation. Attackers leverage buffer overflows for switch RCE and abuse named pipes for SYSTEM https://t.co/vQpN7DRF3C https://t.co/QC14eBVf0C
@2Workly
22 Sept 2026
5 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
CISA added Zyxel GS1900 to KEV yesterday: CVE-2026-7273. Unauthenticated LAN attacker, crafted HTTP to the CGI, possible OS command execution. Federal due date Sep 24. Forensic triage required.
@Sunil_kumawat17
22 Sept 2026
15 Impressions
0 Retweets
0 Likes
0 Bookmarks
1 Reply
0 Quotes
🔐 Daily Security & Standards Brief (Sep 21) CVE-2026-7273--Zyxel GS1900 Series Switches Stack-Based Buffer Overflow: patch Zyxel GS1900 Series Switches Stack-Based Buffer Overflow and verify the fix held. Full digest 👇 via PCMedicalist #CyberSecurity #InfoSec https://t
@PCMedicalist
22 Sept 2026
24 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
🔒 #CyberSecurity CVE-2026-7273: Zyxel GS1900 Switch Buffer Overflow Actively Exploited — CISA KE… "On September 21, 2026, CISA added CVE-2026-7273 — a stack-based buffer overflow vulnerability…" 🔗 https://t.co/hU1XggLG0g #CyberSecurity #ThreatIntel #critical #ze
@SecurityAr58409
22 Sept 2026
50 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
🔒 #CyberSecurity CVE-2026-7273: Zyxel GS1900 Switch Buffer Overflow Actively Exploited — Detecti… "On September 21, 2026, CISA added CVE-2026-7273 to the Known Exploited Vulnerabilities…" 🔗 https://t.co/AEnljNqQic #CyberSecurity #ThreatIntel #cve20267273 #critical
@SecurityAr58409
22 Sept 2026
42 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
CISA adds CVE-2026-7273, a stack buffer overflow in Zyxel GS1900 switches, to its Known Exploited Vulnerabilities Catalog. Active exploitation confirmed—patch now and comply with BOD 26-04 to secure your network. #CISA #Zyxel #PatchManagement #SOCMinute https://t.co/nVWHl2tFi1
@SOCMinute
21 Sept 2026
47 Impressions
0 Retweets
1 Like
0 Bookmarks
0 Replies
0 Quotes
🚨 CVE-2026-7273 — HIGH — actively exploited per CISA KEV Zyxel GS1900 Series Switches CVSS 8.8 | EPSS 0% #Zyxel #CVE https://t.co/veTQUt9RWa
@threatpodium
21 Sept 2026
5 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
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