CVE-2026-82616Public exploitNetwork attack vectorHinoki check available

Authenticated process crash via oversized FileName

Published Aug 31, 2026 · Updated Aug 31, 2026

Stack-based buffer overflow in TOTOLINK NR1800X Firmware 9.1.0u.6681_B20230703 allows remote authenticated users to crash cstecgi.cgi. The setUploadSetting function in /cgi-bin/cstecgi.cgi places an overlong FileName value into a fixed-size stack buffer without validating its length. The published assessment requires low privileges and no user interaction; the established consequences are stack memory corruption and process failure.

CVSS severity9.9
Critical
EPSS probability0.61%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Stack-based buffer overflow in TOTOLINK NR1800X Firmware 9.1.0u.6681_B20230703 allows remote authenticated users to crash cstecgi.cgi. The setUploadSetting function in /cgi-bin/cstecgi.cgi places an overlong FileName value into a fixed-size stack buffer without validating its length. The published assessment requires low privileges and no user interaction; the established consequences are stack memory corruption and process failure.

The record

CVE
CVE-2026-82616
Published
Aug 31, 2026
Updated
Aug 31, 2026
Vendor
TOTOLINK
Product
NR1800X Firmware
Classifications
CWE-119, CWE-121, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 31, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 31, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=9.1.0u.6681_B20230703

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

TOTOLINK · NR1800X Firmwareversion=9.1.0u.6681_B20230703

Published CVSS scores

9.9VulDB CNACVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
9.0VulDB CNAAV:N/AC:L/Au:S/C:C/I:C/A:C
8.6VulDB CNACVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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.

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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-119Improper Restriction of Operations within the Bounds of a Memory Buffer
CWE-121Stack-based Buffer Overflow
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

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Your stack

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