| Titre | DrayTek Vigor2960 Vigor2960 1.5.1.6 (revision 8218) Authenticated check_file_exist Heap Memory Corruption |
|---|
| Description | check_file_exist appends the user-controlled upload_name to the buffer associated with another CGI parameter without checking the destination capacity. The current PoC uses the device's existing valid UCI package /etc/config-default/general_conf: an 8-byte upload_name returns normal JSON, while a 0x100-byte input makes the same CGI request return an empty body. A previously captured ARM core further confirms memory corruption and a SIGSEGV during CGI cleanup.
Affected interface: POST /cgi-bin/mainfunction.cgi with action=check_file_exist
Attacker-controlled parameter: upload_name
Confirmed impact: an authenticated attacker can corrupt CGI process memory and crash the current mainfunction.cgi process.
## Vendor Confirmation
The vulnerability has been officially confirmed. The email is available at: https://github.com/yikesoftware/DrayTek_Vigor2960_Security_Analysis/tree/main/vendor_confirm
The official fix for this vulnerability has been released: https://fw.draytek.com.tw/Vigor2960/Firmware/v1.5.1.7/Vigor2960_v1.5.1.7.zip |
|---|
| La source | ⚠️ https://github.com/yikesoftware/DrayTek_Vigor2960_Security_Analysis/tree/main/cases/DRV2960-0020-authenticated-check-file-exist-direct-cgi-core |
|---|
| Utilisateur | eqqie (UID 101441) |
|---|
| Soumission | 20/10/2026 08:16 (il y a 26 jours) |
|---|
| Modérer | 14/11/2026 19:13 (25 days later) |
|---|
| Statut | Accepté |
|---|
| Entrée VulDB | 437464 [DrayTek Vigor2960 1.5.1.6 File Existence Check mainfunction.cgi check_file_exist upload_name buffer overflow] |
|---|
| Points | 20 |
|---|