CVE-2026-5102Public exploitNetwork attack vector

Authenticated command execution via unsanitized QoS bandwidth

Published Mar 30, 2026 · Updated Mar 30, 2026

Command injection in TOTOLINK A3300R 17.0.0cu.557_b20221024 allows remote authenticated users to execute OS commands. The setSmartQosCfg handler in /cgi-bin/cstecgi.cgi inserts the qos_up_bw value into a command string that reaches CsteSystem and execv without validation. A valid SESSION_ID is required, and successful requests run attacker-selected commands with the router service's privileges.

CVSS severityUnavailable
Unscored
EPSS probability2.38%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Command injection in TOTOLINK A3300R 17.0.0cu.557_b20221024 allows remote authenticated users to execute OS commands. The setSmartQosCfg handler in /cgi-bin/cstecgi.cgi inserts the qos_up_bw value into a command string that reaches CsteSystem and execv without validation. A valid SESSION_ID is required, and successful requests run attacker-selected commands with the router service's privileges.

The record

CVE
CVE-2026-5102
Published
Mar 30, 2026
Updated
Mar 30, 2026
Vendor
TOTOLINK
Product
A3300R
Classifications
CWE-77, CWE-74, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 30, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 30, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=17.0.0cu.557_b20221024

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

TOTOLINK · A3300Rversion=17.0.0cu.557_b20221024

Published CVSS scores

6.3VulDBCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
6.3VulDBCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
6.5VulDBAV:N/AC:L/Au:S/C:P/I:P/A:P/E:POC/RL:ND/RC:UR
5.3VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-77Command Injection
CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo