CVE
Shenzhen Cudy TR3000 root command execution in TR-098 username handling
Affects Cudy TR3000 1.0 firmware before 2.5.42 on routers managed by an ACS that sends SetParameterValues requests. Fixed in 2.5.42.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
- Exploited
- No known exploitation
- Fix
- Fixed in 2.5.42
- Who is exposed
- Not reported
Do first: Upgrade to a fixed version: 2.5.42.
- Last modified
- Whether it needs action now or is a reference record, by fixed rules, with why. Last checked is when cve.now last re-read it.What do these mean? →
- Reference
- Last checked
- FIRST's estimate of the chance attackers exploit it in the next 30 days, updated daily.What do these mean? →
- 1.57% · 75th percentile
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 26/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Unclear
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
The Cudy TR3000 has an OS command injection flaw in how it handles TR-098 usernames, which lets a malicious or compromised ACS run commands as root. An attacker can reach it remotely over the network, without logging in, by sending a SetParameterValues request with shell metacharacters in the username value.
Original description
Cudy TR3000 before 2.5.42 contains an OS command injection vulnerability that allows a malicious or compromised ACS to execute commands as root by supplying an unvalidated InternetGatewayDevice.User.{i}.Username value. Attackers can send a SetParameterValues request with shell metacharacters that set_UserUsername() in obuspa_system.lua passes to os.execute(), gaining root command execution.
Who should check
Anyone running Cudy TR3000 1.0 firmware before 2.5.42, or managing these routers through a TR-098 ACS.
“Affecting TR3000 1.0 >= 0, < 2.5.42”
cve.now Index
- Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
- Exposure17/25No login or user action needed, reachable over the network without a login · Unknown: Advisories don't say whether default setups are affected
- Reach?/20Unknown. No tracked technology or package matched
- Severity9.2/10CVSS 9.2
- No patch0/5No signal
What would change the score
- Would score about 71 if added to CISA KEV
- Would score about 66 if CISA's SSVC rates exploitation active
- Would score about 31 if advisories confirm default setups are exposed
What to do
Upgrade to a fixed version: 2.5.42.
Check your systems with an agent
Paste this into a coding or ops agent. It checks your systems read-only and reports a table per asset.
Check whether my systems are affected by CVE-2026-126953 (Cudy TR3000 before 2.5.42 OS Command Injection via TR-098 User Username), using the cve.now data below.
Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only.
What cve.now has for CVE-2026-126953 (entry last updated 2026-11-13):
Affected:
- Shenzhen Cudy Technology Co., Ltd. TR3000 1.0: fixed in 2.5.42
Fixed versions: 2.5.42.
Conditions (all must be true for the bug to be hit):
- Cudy TR3000 firmware before 2.5.42 (TR3000 1.0). (source: https://www.vulncheck.com/advisories/cudy-tr3000-before-2.5.42-os-command-injection-via-tr-098-user-username)
- The device is managed by an ACS that sends SetParameterValues requests (TR-098 User Username parameter). (source: https://www.vulncheck.com/advisories/cudy-tr3000-before-2.5.42-os-command-injection-via-tr-098-user-username)
Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory.
Attacker needs: network access, no login, no user action.
CISA KEV: CVE-2026-126953 is not listed as of cve.now's last read.
This KEV status is for CVE-2026-126953 only. If you also check another CVE, look up its own KEV status; never assume it from this one.
How to check:
- Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory.
Verify against the linked advisories before concluding, and cite the date you read each one:
- https://d1jvyy13vm72kv.cloudfront.net/device/upgrade/m_upgrade_TR3000_256MB_Flash-R103-2.5.42-20261103-160202-sysupgrade_82672.zip
- https://www.cudy.com/en-us/pages/download-center/tr3000-1-0
- https://www.vulncheck.com/advisories/cudy-tr3000-before-2.5.42-os-command-injection-via-tr-098-user-username
Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing.
Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action.
Entry: https://cve.now/CVE-2026-126953
For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example execute with name cve.get and arguments {"id": "CVE-2026-126953"}.Timeline
- CVE published
- First seen by cve.now
- Posted on X by cve.now
Affected versions
- Shenzhen Cudy Technology Co., Ltd. TR3000 1.0
fixed in 2.5.42
Evidence 5
Vendor advisory · 1
Establishes: Affected and fixed versions.
- Link
CVE record · 2
Establishes: The identifier and description.
- Record
- Record
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-126953
Is CVE-2026-126953 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
The flaw is an OS command injection that lets a malicious or compromised ACS run commands as root on the router. The injection happens through the TR-098 User Username parameter.Source: vulncheck.com
Which versions are affected by CVE-2026-126953?
TR3000 1.0: before 2.5.42.Source: cve.now feed data
Am I affected, and how do I check?
Cudy TR3000 1.0 firmware before 2.5.42 is affected, in setups where the router is managed by an ACS that sends SetParameterValues requests with the TR-098 User Username parameter. To check, compare the firmware version shown on the device with 2.5.42.Source: vulncheck.com
How do I fix CVE-2026-126953?
Upgrade the TR3000 firmware to 2.5.42, the fixed version named in the advisory.Source: vulncheck.com