How severe is CVE-2021-26753?

CVE-2021-26753 has a CVSS 3.x base score of 9.9, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-26753 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-26753?

CVE-2021-26753 affects Nedi. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-26753?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-26753 published?

CVE-2021-26753 was published on 2021-02-12 and last updated on 2026-06-17.

CVE-2021-26753

CVE-2021-26753 is a critical-severity vulnerability in Nedi with a CVSS 3.x base score of 9.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-863.

Key facts

Severity: Critical (CVSS 3.x base score 9.9)
CVSS v2: 6.5
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-863
Affected product: Nedi
Published: 2021-02-12
Last modified: 2026-06-17

Description

NeDi 1.9C allows an authenticated user to inject PHP code in the System Files function on the endpoint /System-Files.php via the txt HTTP POST parameter. This allows an attacker to obtain access to the operating system where NeDi is installed and to all application data.

Frequently asked questions

What is CVE-2021-26753?: NeDi 1.9C allows an authenticated user to inject PHP code in the System Files function on the endpoint /System-Files.php via the txt HTTP POST parameter. This allows an attacker to obtain access to the operating system where NeDi is installed and to all application data.
How severe is CVE-2021-26753?: CVE-2021-26753 has a CVSS 3.x base score of 9.9, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-26753 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-26753?: CVE-2021-26753 affects Nedi. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-26753?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-26753 published?: CVE-2021-26753 was published on 2021-02-12 and last updated on 2026-06-17.

References

https://n4nj0.github.io/advisories/nedi-multiple-vulnerabilities-i/

Affected products (1)

cpe:2.3:a:nedi:nedi:1.9c:*:*:*:*:*:*:*

More vulnerabilities in Nedi

CVE-2022-40895 — Critical (CVSS 9.1): In certain Nedi products, a vulnerability in the web UI of NeDi login & Community login could allow an unauthenticated,…
CVE-2021-26752 — High (CVSS 8.8): NeDi 1.9C allows an authenticated user to execute operating system commands in the Nodes Traffic function on the…
CVE-2021-26751 — High (CVSS 8.8): NeDi 1.9C allows an authenticated user to perform a SQL Injection in the Monitoring History function on the endpoint…
CVE-2020-14414 — High (CVSS 8.8): NeDi 1.9C is vulnerable to Remote Command Execution. pwsec.php improperly escapes shell metacharacters from a POST…
CVE-2020-14412 — High (CVSS 8.8): NeDi 1.9C is vulnerable to Remote Command Execution. System-Snapshot.php improperly escapes shell metacharacters from a…
CVE-2018-20728 — High (CVSS 8.8): A cross site request forgery (CSRF) vulnerability in NeDi before 1.7Cp3 allows remote attackers to escalate privileges…

All CVEs affecting Nedi →

Other CWE-863 (Incorrect Authorization) vulnerabilities

CVE-2026-48286 — Critical (CVSS 10.0): Adobe Campaign Classic (ACC) versions 7.4.3 build 9396 and earlier are affected by an Incorrect Authorization…
CVE-2026-48303 — Critical (CVSS 10.0): Adobe Campaign Classic (ACC) versions 7.4.3 build 9394 and earlier are affected by an Incorrect Authorization…
CVE-2026-44330 — Critical (CVSS 10.0): free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the…
CVE-2026-46595 — Critical (CVSS 10.0): Previously, CVE-2024-45337 fixed an authorization bypass for misused ssh server configurations; if any other type of…
CVE-2026-33105 — Critical (CVSS 10.0): Improper authorization in Microsoft Azure Kubernetes Service allows an unauthorized attacker to elevate privileges over…
CVE-2026-32213 — Critical (CVSS 10.0): Improper authorization in Azure AI Foundry allows an unauthorized attacker to elevate privileges over a network.

Browse all CWE-863 (Incorrect Authorization) vulnerabilities →