CVE-2026-1326VulnerabilityPublished 22 Jan 2026Updated 23 Feb 2026

CVE-2026-1326: Totolink NR1800X · Command Injection

Affects Totolink NR1800XSource CVE Database V5

Not known to be exploited · CVSS 5.3 Medium.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 4.0 base score

5.3Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 3.4% chance of exploitation in 30 days – higher than 89% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS: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

Base metrics

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: None
Privileges Required: Low
User Interaction: None
Vulnerable system confidentiality: Low
Vulnerable system integrity: Low
Vulnerable system availability: Low
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

Threat metrics

Exploit Maturity: POC

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, up to and including the entire Internet. Such a vulnerability is often termed “remotely exploitable” and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: Low: The attacker requires privileges that provide basic capabilities that are typically limited to settings and resources owned by a single low-privileged user. Alternatively, an attacker with Low privileges has the ability to access only non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without interaction from any human user, other than the attacker.
Vulnerable system confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the Vulnerable System.
Vulnerable system integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact to the Vulnerable System.
Vulnerable system availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the Vulnerable System are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the Vulnerable System.
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.
Exploit Maturity: POC: Based on threat intelligence sources each of the following must apply: · Proof-of-concept is publicly available · No knowledge of reported attempts to exploit this vulnerability · No knowledge of publicly available solutions used to simplify attempts to exploit the vulnerability

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 22 Jan 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
TotolinkNR1800X	Affected =9.1.0u.6279_B20210910	Fixed in–

AI-suggested

To mitigate CVE-2026-1326, organizations should first verify if they are running the affected firmware version 9.1.0u.6279_B20210910 on Totolink NR1800X routers. If so, they should immediately check for any official firmware updates or patches from Totolink addressing this vulnerability and apply them as soon as they become available. In the absence of an official patch, network administrators should restrict access to the router's management interface by limiting it to trusted internal networks and disabling remote management over the internet. Implementing network segmentation to isolate vulnerable devices can reduce the risk of lateral movement. Monitoring router logs and network traffic for suspicious activity related to the /cgi-bin/cstecgi.cgi endpoint or unusual command execution attempts is recommended. Additionally, changing default credentials and enforcing strong authentication mechanisms can help reduce the attack surface. If feasible, consider replacing affected devices with models that have no known vulnerabilities or have been patched. Finally, educating users about the risks and signs of router compromise can aid early detection and response.

Description

A weakness has been identified in Totolink NR1800X 9.1.0u.6279_B20210910. This vulnerability affects the function setWanCfg of the file /cgi-bin/cstecgi.cgi of the component POST Request Handler. This manipulation of the argument Hostname causes command injection. The attack can be initiated remotely. The exploit has been made available to the public and could be used for attacks.

Impact

The exploitation of CVE-2026-1326 can have significant consequences for organizations and individuals using the affected Totolink NR1800X router firmware. Attackers could gain the ability to execute arbitrary commands on the router remotely, leading to full device compromise. This could result in interception or manipulation of network traffic, disruption of internet connectivity, unauthorized access to internal networks, and potential lateral movement to other devices. For small businesses and home users, this could mean loss of confidentiality and integrity of sensitive data, as well as denial of service. In environments where these routers are deployed as part of critical infrastructure or branch office networks, the impact could extend to operational disruptions and increased risk of broader network breaches. The medium CVSS score reflects the moderate ease of exploitation combined with partial impact on confidentiality, integrity, and availability. However, the availability of public exploit code raises the likelihood of exploitation attempts, increasing the urgency for mitigation.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 23 Feb 2026, 22:23 UTC

Technical details

References

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