How severe is CVE-2019-18873?

CVE-2019-18873 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2019-18873 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 8% (94th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-18873?

CVE-2019-18873 affects Fudforum. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-18873?

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-2019-18873 published?

CVE-2019-18873 was published on 2019-11-12 and last updated on 2026-06-17.

CVE-2019-18873

CVE-2019-18873 is a critical-severity vulnerability in Fudforum with a CVSS 3.x base score of 9.0. 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-78.

Key facts

Severity: Critical (CVSS 3.x base score 9.0)
CVSS v2: 8.5
EPSS exploit prediction: 8% (94th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Fudforum
Published: 2019-11-12
Last modified: 2026-06-17

Description

FUDForum 3.0.9 is vulnerable to Stored XSS via the User-Agent HTTP header. This may result in remote code execution. An attacker can use a user account to fully compromise the system via a GET request. When the admin visits user information under "User Manager" in the control panel, the payload will execute. This will allow for PHP files to be written to the web root, and for code to execute on the remote server. The problem is in admsession.php and admuser.php.

Frequently asked questions

What is CVE-2019-18873?: FUDForum 3.0.9 is vulnerable to Stored XSS via the User-Agent HTTP header. This may result in remote code execution. An attacker can use a user account to fully compromise the system via a GET request. When the admin visits user information under "User Manager" in the control panel, the payload will execute. This will allow for PHP files to be written to the web root, and for code to execute on the remote server. The problem is in admsession.php and admuser.php.
How severe is CVE-2019-18873?: CVE-2019-18873 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2019-18873 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 8% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-18873?: CVE-2019-18873 affects Fudforum. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-18873?: 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-2019-18873 published?: CVE-2019-18873 was published on 2019-11-12 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:fudforum:fudforum:3.0.9:*:*:*:*:*:*:*

More vulnerabilities in Fudforum

CVE-2019-18839 — Critical (CVSS 9.0): FUDForum 3.0.9 is vulnerable to Stored XSS via the nlogin parameter. This may result in remote code execution. An…
CVE-2022-30860 — High (CVSS 7.2): FUDforum 3.1.2 is vulnerable to Remote Code Execution through Upload File feature of File Administration System in…
CVE-2013-2267 — High (CVSS 7.2): PHP Code Injection vulnerability in FUDforum Bulletin Board Software 3.0.4 could allow remote attackers to execute…
CVE-2024-30951 — Medium (CVSS 6.1): FUDforum v3.1.3 was discovered to contain a reflected cross-site scripting (XSS) vulnerability via the chpos parameter…
CVE-2021-27520 — Medium (CVSS 6.1): A cross-site scripting (XSS) issue in FUDForum 3.1.0 allows remote attackers to inject JavaScript via index.php in the…
CVE-2021-27519 — Medium (CVSS 6.1): A cross-site scripting (XSS) issue in FUDForum 3.1.0 allows remote attackers to inject JavaScript via index.php in the…

All CVEs affecting Fudforum →

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