Unauthenticated code execution via citytag stack overflow
Published Jan 21, 2026 · Updated Jan 21, 2026
Stack-based buffer overflow in Tenda AX3 firmware 16.03.12.11 allows remote attackers to execute code through a crafted citytag value. The formGetIptv handler processes the untrusted citytag value without enforcing the capacity of its stack buffer, corrupting adjacent stack memory. No authentication or user interaction is required, and successful exploitation runs attacker-controlled code on the router.
Summary
What happened
Stack-based buffer overflow in Tenda AX3 firmware 16.03.12.11 allows remote attackers to execute code through a crafted citytag value. The formGetIptv handler processes the untrusted citytag value without enforcing the capacity of its stack buffer, corrupting adjacent stack memory. No authentication or user interaction is required, and successful exploitation runs attacker-controlled code on the router.
The record
- CVE
- CVE-2025-69766
- Published
- Jan 21, 2026
- Updated
- Jan 21, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-121, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 21, 2026CVE publishedPublication date reported by the CVE source.
- Jan 21, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Tenda AX3 Buffer Overflow in formGetIptv proof of conceptproof of concept · unverified
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Technologies
Your stack
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Your stack
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