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TI-2021-13997 Aliases CVE-2021-35031GHSA-xghr-m3mr-m6m9

OS command injection in Zyxel GS1900 series firmware

Priority LOW 35CWE-78Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-78.

Summary

A vulnerability in the TFTP client of Zyxel GS1900 series firmware, XGS1210 series firmware, and XGS1250 series firmware, which could allow an authenticated LAN user to execute arbitrary OS commands via the GUI of the vulnerable device.

Why it matters now

EPSS 0.00478 41st percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
ZyxelGS1900 series firmware2.60—No fix listedCNA
ZyxelXGS1210 series firmware1.00(ABTY.4)C0—No fix listedCNA
ZyxelXGS1250 series firmware1.00(ABWE.0)C0—No fix listedCNA
  • GS1900 series firmware VendorZyxel Affected 2.60 Fixed in — No fix listed CNA
  • XGS1210 series firmware VendorZyxel Affected 1.00(ABTY.4)C0 Fixed in — No fix listed CNA
  • XGS1250 series firmware VendorZyxel Affected 1.00(ABWE.0)C0 Fixed in — No fix listed CNA

CPE configurations NVD · 28

CPEVersionsRoleVendor
cpe:2.3:o:zyxel:gs1900-8_firmware:*:*:*:*:*:*:*:*before 2.70\(aahh.0\)-20211208VulnerableZyxel
cpe:2.3:h:zyxel:gs1900-8:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:o:zyxel:gs1900-8hp_firmware:*:*:*:*:*:*:*:*before 2.70\(aahi.0\)-20211208VulnerableZyxel
cpe:2.3:h:zyxel:gs1900-8hp:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:o:zyxel:gs1900-10hp_firmware:*:*:*:*:*:*:*:*before 2.70\(aazi.0\)-20211208VulnerableZyxel
cpe:2.3:h:zyxel:gs1900-10hp:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:o:zyxel:gs1900-16_firmware:*:*:*:*:*:*:*:*before 2.70\(aahj.0\)-20211208VulnerableZyxel
cpe:2.3:h:zyxel:gs1900-16:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:o:zyxel:gs1900-24e_firmware:*:*:*:*:*:*:*:*before 2.70\(aahk.0\)-20211208VulnerableZyxel
cpe:2.3:h:zyxel:gs1900-24e:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
  • cpe:2.3:o:zyxel:gs1900-8_firmware:*:*:*:*:*:*:*:* Versions before 2.70\(aahh.0\)-20211208 Vulnerable ·Zyxel
  • cpe:2.3:h:zyxel:gs1900-8:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:o:zyxel:gs1900-8hp_firmware:*:*:*:*:*:*:*:* Versions before 2.70\(aahi.0\)-20211208 Vulnerable ·Zyxel
  • cpe:2.3:h:zyxel:gs1900-8hp:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:o:zyxel:gs1900-10hp_firmware:*:*:*:*:*:*:*:* Versions before 2.70\(aazi.0\)-20211208 Vulnerable ·Zyxel
  • cpe:2.3:h:zyxel:gs1900-10hp:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:o:zyxel:gs1900-16_firmware:*:*:*:*:*:*:*:* Versions before 2.70\(aahj.0\)-20211208 Vulnerable ·Zyxel
  • cpe:2.3:h:zyxel:gs1900-16:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:o:zyxel:gs1900-24e_firmware:*:*:*:*:*:*:*:* Versions before 2.70\(aahk.0\)-20211208 Vulnerable ·Zyxel
  • cpe:2.3:h:zyxel:gs1900-24e:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
Show 18 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:zyxel:gs1900-24ep_firmware:*:*:*:*:*:*:*:*before 2.70\(abto.0\)-20211208VulnerableZyxel
cpe:2.3:h:zyxel:gs1900-24ep:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:o:zyxel:gs1900-24_firmware:*:*:*:*:*:*:*:*before 2.70\(aahl.0\)-20211208VulnerableZyxel
cpe:2.3:h:zyxel:gs1900-24:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:o:zyxel:gs1900-24hp_firmware:*:*:*:*:*:*:*:*before 2.70\(aahm.0\)-20211208VulnerableZyxel
cpe:2.3:h:zyxel:gs1900-24hp:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:o:zyxel:gs1900-24hpv2_firmware:*:*:*:*:*:*:*:*before 2.70\(aatp.0\)-20211208VulnerableZyxel
cpe:2.3:h:zyxel:gs1900-24hpv2:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:o:zyxel:gs1900-48_firmware:*:*:*:*:*:*:*:*before 2.70\(aahn.0\)-20211208VulnerableZyxel
cpe:2.3:h:zyxel:gs1900-48:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:o:zyxel:gs1900-48hp_firmware:*:*:*:*:*:*:*:*before 2.70\(aaho.0\)-20211208VulnerableZyxel
cpe:2.3:h:zyxel:gs1900-48hp:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:o:zyxel:gs1900-48hpv2_firmware:*:*:*:*:*:*:*:*before 2.70\(abtq.0\)-20211208VulnerableZyxel
cpe:2.3:h:zyxel:gs1900-48hpv2:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:o:zyxel:xgs1210-12_firmware:*:*:*:*:*:*:*:*before 1.00\(abty.5\)c0VulnerableZyxel
cpe:2.3:h:zyxel:xgs1210-12:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:o:zyxel:xgs1250-12_firmware:*:*:*:*:*:*:*:*before 1.00\(abwe.1\)c0VulnerableZyxel
cpe:2.3:h:zyxel:xgs1250-12:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
  • cpe:2.3:o:zyxel:gs1900-24ep_firmware:*:*:*:*:*:*:*:* Versions before 2.70\(abto.0\)-20211208 Vulnerable ·Zyxel
  • cpe:2.3:h:zyxel:gs1900-24ep:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:o:zyxel:gs1900-24_firmware:*:*:*:*:*:*:*:* Versions before 2.70\(aahl.0\)-20211208 Vulnerable ·Zyxel
  • cpe:2.3:h:zyxel:gs1900-24:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:o:zyxel:gs1900-24hp_firmware:*:*:*:*:*:*:*:* Versions before 2.70\(aahm.0\)-20211208 Vulnerable ·Zyxel
  • cpe:2.3:h:zyxel:gs1900-24hp:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:o:zyxel:gs1900-24hpv2_firmware:*:*:*:*:*:*:*:* Versions before 2.70\(aatp.0\)-20211208 Vulnerable ·Zyxel
  • cpe:2.3:h:zyxel:gs1900-24hpv2:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:o:zyxel:gs1900-48_firmware:*:*:*:*:*:*:*:* Versions before 2.70\(aahn.0\)-20211208 Vulnerable ·Zyxel
  • cpe:2.3:h:zyxel:gs1900-48:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:o:zyxel:gs1900-48hp_firmware:*:*:*:*:*:*:*:* Versions before 2.70\(aaho.0\)-20211208 Vulnerable ·Zyxel
  • cpe:2.3:h:zyxel:gs1900-48hp:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:o:zyxel:gs1900-48hpv2_firmware:*:*:*:*:*:*:*:* Versions before 2.70\(abtq.0\)-20211208 Vulnerable ·Zyxel
  • cpe:2.3:h:zyxel:gs1900-48hpv2:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:o:zyxel:xgs1210-12_firmware:*:*:*:*:*:*:*:* Versions before 1.00\(abty.5\)c0 Vulnerable ·Zyxel
  • cpe:2.3:h:zyxel:xgs1210-12:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:o:zyxel:xgs1250-12_firmware:*:*:*:*:*:*:*:* Versions before 1.00\(abwe.1\)c0 Vulnerable ·Zyxel
  • cpe:2.3:h:zyxel:xgs1250-12:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-35031
  2. 2026-10-03 Alias added: GHSA-xghr-m3mr-m6m9

References

Patch 1

  • TI-2026-06387 Stack-based buffer overflow in Zyxel GS1900-48HPv2 firmware KEVCVSS 3.1HIGH 8.8
  • TI-2019-11869 An issue was discovered on Zyxel GS1900 devices with firmware before 2.50(AAHH.0)C0. CVSS 3.1CRITICAL 9.8
  • TI-2016-01221 Cisco NX-OS 6.0(2)U6(1) through 6.0(2)U6(5) on Nexus 3000 devices and 6.0(2)A6(1) through… CVSS 3.0CRITICAL 9.8
  • TI-2015-05062 Belkin F9K1102 2 devices with firmware 2.10.17 rely on client-side JavaScript code for… CVSS 3.0CRITICAL 9.8
  • TI-2015-05061 The web management interface on Belkin F9K1102 2 devices with firmware 2.10.17 has a… CVSS 3.0CRITICAL 9.8
  • TI-2019-11872 An issue was discovered on Zyxel GS1900 devices with firmware before 2.50(AAHH.0)C0. CVSS 3.1CRITICAL 9.1
See all 34 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences