CVE-2021-35031
HIGH
8
CVSS Score
Published: December 28, 2021 at 10:36 AM UTC
Updated: June 17, 2026 at 03:56 AM UTC
31 products affected across 1 vendorGS1900-10HP firmwareGS1900-24 firmwareGS1900-8 Firmware
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Severity
HIGH8
Exploit prediction
EPSS 0.5%
Description
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.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
v < 2.70(aazi.0)-20211208
Affected range stops below 2.70(aazi.0)-20211208, so it looks safe — our inference, not a vendor statement
zyxel-gs1900-10hp (same device)
v < 2.70(aahj.0)-20211208
Affected range stops below 2.70(aahj.0)-20211208, so it looks safe — our inference, not a vendor statement
zyxel-gs1900-16 (same device)
v < 2.70(aahl.0)-20211208
Affected range stops below 2.70(aahl.0)-20211208, so it looks safe — our inference, not a vendor statement
zyxel-gs1900-24 (same device)
v < 2.70(aahk.0)-20211208
Affected range stops below 2.70(aahk.0)-20211208, so it looks safe — our inference, not a vendor statement
zyxel-gs1900-24e (same device)
v < 2.70(abto.0)-20211208
Affected range stops below 2.70(abto.0)-20211208, so it looks safe — our inference, not a vendor statement
zyxel-gs1900-24ep (same device)
v < 2.70(aahm.0)-20211208
Affected range stops below 2.70(aahm.0)-20211208, so it looks safe — our inference, not a vendor statement
zyxel-gs1900-24hp (same device)
v < 2.70(aatp.0)-20211208
Affected range stops below 2.70(aatp.0)-20211208, so it looks safe — our inference, not a vendor statement
zyxel-gs1900-24hpv2 (same device)
v < 2.70(aahn.0)-20211208
Affected range stops below 2.70(aahn.0)-20211208, so it looks safe — our inference, not a vendor statement
zyxel-gs1900-48 (same device)
v < 2.70(aaho.0)-20211208
Affected range stops below 2.70(aaho.0)-20211208, so it looks safe — our inference, not a vendor statement
zyxel-gs1900-48hp (same device)
v < 2.70(abtq.0)-20211208
Affected range stops below 2.70(abtq.0)-20211208, so it looks safe — our inference, not a vendor statement
zyxel-gs1900-48hpv2 (same device)
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
References (1)
x_refsource_CONFIRMPatchVendor Advisory
Source: [email protected]
https://www.zyxel.com/support/Zyxel_security_advisory_for_OS_command_injection_vulnerabilities_of_switches.shtmlCVSS
- Attack Vector
- ADJACENT_NETWORK
- Complexity
- LOW
- Privileges
- LOW
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality
- HIGH
- Integrity
- HIGH
- Availability
- HIGH
Vector?
Quick Info
StatusMODIFIED
CWE
CWE-78
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