CVE-2026-19341 Overview
CVE-2026-19341 is a stack-based buffer overflow vulnerability in the UTT HiPER 1200GW router through firmware version 2.5.3-170306. The flaw resides in the strcpy call within the /goform/pptpSrvGlobalConfig handler, where the EncryptionMode parameter is copied into a fixed-size stack buffer without bounds checking. Remote attackers with low-privileged access can send a crafted HTTP request to trigger memory corruption. The exploit has been publicly disclosed. The vendor was contacted but did not respond, leaving affected devices without an official fix. The weakness is classified under CWE-119, improper restriction of operations within the bounds of a memory buffer.
Critical Impact
Remote attackers can corrupt stack memory on the router, potentially achieving arbitrary code execution and full device compromise on the network gateway.
Affected Products
- UTT HiPER 1200GW router
- Firmware versions up to and including 2.5.3-170306
- The /goform/pptpSrvGlobalConfig web management endpoint
Discovery Timeline
- 2026-08-09 - CVE-2026-19341 published to NVD
- 2026-08-12 - Last updated in NVD database
Technical Details for CVE-2026-19341
Vulnerability Analysis
The vulnerability affects the web-based management interface of the UTT HiPER 1200GW router. The /goform/pptpSrvGlobalConfig endpoint handles configuration of the Point-to-Point Tunneling Protocol (PPTP) server. When processing this request, the handler invokes strcpy to copy the user-supplied EncryptionMode parameter into a stack-allocated buffer. Because strcpy performs no length validation, an attacker-supplied value exceeding the destination buffer size overwrites adjacent stack memory. This corruption includes saved return addresses and local control data. Successful exploitation can redirect execution flow, resulting in arbitrary code execution on the embedded device. The public disclosure of exploitation details increases the likelihood of opportunistic attacks against exposed devices.
Root Cause
The root cause is the unsafe use of the strcpy C standard library function on attacker-controlled input. The developer did not enforce a maximum length on the EncryptionMode field before copying it. Safer alternatives such as strncpy or snprintf with explicit size bounds would have prevented the overflow. This pattern is characteristic of [CWE-119] boundary violations common in consumer and small-business router firmware.
Attack Vector
Exploitation requires network reachability to the router's web administration interface and a low-privileged authenticated session. An attacker sends a crafted HTTP POST request to /goform/pptpSrvGlobalConfig containing an oversized EncryptionMode parameter. If the management interface is exposed to the WAN, the attack is remotely executable across the internet. When only accessible from the LAN, an attacker with foothold on any internal host can pivot to the router. Verified technical analysis is available in the GitHub CVE Analysis and VulDB Vulnerability Details.
Detection Methods for CVE-2026-19341
Indicators of Compromise
- HTTP POST requests to /goform/pptpSrvGlobalConfig containing abnormally long EncryptionMode values.
- Unexpected reboots, crashes, or watchdog resets of the UTT HiPER 1200GW router coinciding with inbound management traffic.
- Configuration changes to PPTP server settings not initiated by administrators.
- New or unexpected outbound connections from the router to unknown external hosts.
Detection Strategies
- Inspect HTTP traffic to the router's management interface with network intrusion detection signatures targeting oversized parameters in /goform/ URIs.
- Correlate router syslog events showing crash traces or PPTP service restarts against inbound HTTP activity.
- Alert on any WAN-side access attempts to the router's administrative HTTP interface.
Monitoring Recommendations
- Forward router logs to a central SIEM and monitor for repeated /goform/pptpSrvGlobalConfig requests from a single source.
- Baseline normal administrative traffic patterns to detect anomalous parameter lengths or user-agents.
- Monitor for changes to router credentials, DNS settings, and routing tables that could indicate post-exploitation activity.
How to Mitigate CVE-2026-19341
Immediate Actions Required
- Disable remote WAN-side access to the router's web management interface immediately.
- Restrict LAN access to the management interface using an access control list that permits only trusted administrative IP addresses.
- Rotate all administrative credentials on affected UTT HiPER 1200GW devices.
- Where feasible, replace the affected device with a supported router, since the vendor has not responded to disclosure.
Patch Information
No vendor patch is available at the time of publication. According to the disclosure record on VulDB CVE Entry, the vendor was contacted early but did not respond. Organizations operating affected devices should assume no fix will be released and plan device replacement or strict network segmentation.
Workarounds
- Place affected routers behind an upstream firewall that blocks unsolicited inbound traffic to the management interface.
- Disable the PPTP server feature on the router if it is not required, reducing the attack surface of the vulnerable handler.
- Segment the router's management VLAN and require VPN access from a hardened jump host for administrative sessions.
- Consider retiring the device in favor of a vendor-supported platform that receives security updates.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
