CVE-2026-1162: Unauthenticated Remote Code Execution via Password Buffer Overflow in UTT HiPER 810

CVE-2026-1162 — UTT HiPER 810 Remote Buffer Overflow Leading to RCE

CVE: CVE-2026-1162
Product: UTT HiPER 810
Vulnerability: Buffer Overflow in Web Management Handler
Severity: Critical (CVSS 3.1 9.8)
Impact: Remote code execution (RCE) via crafted HTTP request
Exploitability: Remote, network accessible, unauthenticated
Exploit Availability: Public proof-of-concept (PoC) present in third-party repositories

What’s Broken and Why It’s Serious

At its core this vulnerability is a buffer overflow in the firmware of the UTT HiPER 810 router in how it processes requests to its internal management web interface:

The affected code improperly uses a function (strcpy) that blindly copies input data into a fixed-sized memory buffer without checking the length.
This occurs in the handler for the web form endpoint /goform/setSysAdm, specifically involving the passwd1 parameter.
When an attacker sends an HTTP request to the management endpoint with a very long string for passwd1, the code overruns the allocated buffer in memory.
Because the overflow corrupts stack memory and adjacent execution structures, an attacker can influence program control flow and potentially take control of the device’s CPU — effectively achieving remote code execution (RCE).

This is not just a denial-of-service-style crash: the context and nature of the overflow means arbitrary commands and code could be run on the router’s operating environment.

Attack Requirements

In plain terms, an attacker needs:

✔ Network access to the router’s web management interface
✔ No valid credentials or login are required — unauthenticated access is enough
✔ The ability to issue an HTTP POST or GET to the vulnerable endpoint with crafted values

In practical terms:

If the router’s web GUI is publicly routable on the Internet, this vulnerability is extremely dangerous because attackers won’t need local network access.
Even within internal networks, any untrusted host that can reach the management interface could exploit this flaw.

How Exploits Work

To exploit the flaw, an attacker crafts an HTTP request to the router like this:

POST /goform/setSysAdm HTTP/1.1
Host: <router_ip>
Content-Type: application/x-www-form-urlencoded

passwd1=<very_long_string>&other_fields=…

The passwd1 field normally carries a new password string.
When the server code receives this field, it calls strcpy() to copy that input into a local buffer.
strcpy() does no length checking — if the attacker supplies a string longer than the buffer’s capacity, memory beyond the buffer is overwritten.
By carefully choosing how long and what content is in that overwrite region, the attacker can make the router jump to code of their choosing.

This is the classic stack buffer overflow exploited in many older systems, but here it’s exposed on an embedded network device with administrative privileges.

How to Detect Exploitation Attempts

There are two angles to detection: attempts and successful exploitation.

1. HTTP and Network Indicators

Watch for:

HTTP requests to /goform/setSysAdm containing:
- Abnormally long passwd1 strings (> normal human lengths)
- Repeated high-frequency requests to this endpoint
- Heavy requests from unusual source IPs
Requests from outside trusted admin IP ranges

Suggested SIEM search templates:

Splunk

index=network sourcetype=proxy OR sourcetype=web_access
uri="/goform/setSysAdm"
| stats count by src_ip, uri_query
| where len(uri_query) > 200

Elasticsearch (KQL)

http.request.path : "/goform/setSysAdm" AND http.request.body.bytes > 200

Zeek HTTP logs

event Http::log_http {
   if ( uri == "/goform/setSysAdm" && (body_length > 200) )
      NOTICE([$note="SuspiciousHiPER810PasswordOverflow", $src=id$orig_h, $dst=id$resp_h]);
}

These examples are for defenders — they do not contain exploit payloads but instead focus on unusual request properties that deviate from normal use.

2. Device Behavior Patterns

If exploitation is attempted or successful:

Unexpected router process restarts or crashes
Logging of corrupted memory exceptions, stack dumps, or watchdog resets
New/open listening ports that weren’t present before
Outbound connections initiated from the router to external hosts
Configuration changes that were not authorized

How to Recognize a PoC in the Wild

Public PoCs for CVE-2026-1162 are simple scripts that directly target the vulnerable password handler in the HiPER 810 web interface.

Key indicators to watch for:

Direct access to /goform/setSysAdm
Requests go straight to this endpoint with no prior login, session setup, or normal UI navigation.
Abnormally large passwd1 values
The passwd1 parameter contains hundreds or thousands of characters — far beyond any legitimate password length.
Repetitive, machine-generated payloads
Long strings of repeated characters or identical payload sizes sent multiple times in quick succession.
Non-text or malformed input
Presence of binary-looking data, non-ASCII characters, or heavily URL-encoded values inside passwd1.
Encoding abuse
Payload inflation through excessive or mixed URL encoding to bypass simple filters.
High-frequency attempts
Multiple nearly identical requests sent rapidly from the same source, typical of automated PoC scripts.
Immediate device instability
Web service crashes, router reboots, or management interface resets shortly after the request is received.

Detection focus:
Do not rely on matching exact strings. For this vulnerability, the most reliable signals are endpoint misuse, unrealistic password lengths, and automation-style request patterns.ve.

Post-Exploit Indicators

Even if you block the initial exploit attempt, if the router has already been compromised before patching:

Admin accounts or passwords changed without authorization
Firmware version suddenly different than expected
New scheduled tasks, cron jobs, or persistent binaries in the system
Outbound traffic on unusual ports
Abnormal CPU usage spikes without normal reason

If any of these appear on routers that were exposed externally, assume compromise until proven otherwise and isolate immediately.

Practical Mitigations Until You Patch

If a patch isn’t yet installed:

Block HTTP/management access at the firewall level to prevent outsider reach.
Restrict access to trusted admin IPs only.
Disable remote management unless absolutely necessary.
Monitor access logs for the patterns above.
Segment management interfaces away from general network traffic.
Change admin passwords after confirming device integrity.

These steps reduce the risk window between discovery and patching.

Important Notes

This vulnerability is not limited to authenticated users — anyone who can reach the endpoint could attempt an exploit.
Buffer overflows allow full control if successfully exercised, not just a crash or denial of service.
There are unsafe PoCs floating publicly — defenders should only run them in isolated labs with no production connectivity.

Official Patch/Upgrade

The only official, trusted update for affected UTT HiPER devices will come directly from the vendor — either as a firmware release or support guidance.

Download UTT firmware / support: https://www.uttglobal.com/

If a direct CVE-specific firmware is not yet visible on that site, contact UTT support and request the patched version for CVE-2026-1162.

Final Takeaway

CVE-2026-1162 is a critical buffer overflow in the UTT HiPER 810 router’s web management interface that can let an attacker take full control remotely. It needs to be addressed swiftly through vendor-provided firmware updates and mitigated via network controls in the meantime. The techniques defenders use to detect and stop this are primarily about watching for unusual HTTP requests and abnormal router behavior.