CVE-2026-54364: Improper Encoding (CVSS 6.5)

Description

CentreStack before 17.4 contains a session variable injection vulnerability that allows unauthenticated attackers to inject arbitrary session variables by embedding newline and tab characters into a crafted AccountName parameter posted to the SelectProvider.aspx endpoint. Attackers can exploit the lack of input sanitization in the custom session serialization format to inject a resellerid session variable, bypassing the IsValidRSession authentication check and gaining unauthorized access to management pages.

Is your site exposed to CVE-2026-54364?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

6.5

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

EPSS — Exploit Prediction

0.0025

Probability of exploitation

0.16%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-116 CWE-116

References

Other References

https://www.centrestack.com/ https://www.vulncheck.com/advisories/centrestack-session-injection-via-selectprovider-aspx

Frequently Asked Questions

What is CVE-2026-54364? +

CentreStack before 17.4 contains a session variable injection vulnerability that allows unauthenticated attackers to inject arbitrary session variables by embedding newline and tab characters into a crafted AccountName parameter posted to the SelectProvider.aspx endpoint. Attackers can exploit the lack of input sanitization in the custom session serialization format to inject a resellerid session variable, bypassing the IsValidRSession authentication check and gaining unauthorized access to management pages. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2026-54364? +

CVE-2026-54364 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0025, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-54364? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-53693

A stored cross-site scripting vulnerability existed in MISP BSimVis tag rendering code. Several client-side rendering paths interpolated tag names, collection …

CVE-2026-12496

Stored Cross-Site Scripting (CWE-79) in the OPC XML-DA server statistics in Loytec LIP-ME201C, L-INX, L-GATE, L-ROC, L-IOB, L-DALI, L-VIS and …

CVE-2026-59727

Astro is a web framework for content-driven websites. In versions 3.10.0 through 7.0.3, when a transition:persist, transition:scope, or transition:persist-props directive …

CVE-2026-42321

GLPI is a free asset and IT management software package. Starting in version 10.0.4 and prior to version 10.0.25, a …

CVE-2026-58487

HedgeDoc is an open source, real-time, collaborative, markdown notes application. Prior to version 1.11.0, due to unsafe handling of the …

CVE-2026-54893

URL path injection in the Microsoft Graph adapter of Swoosh. Swoosh.Adapters.MsGraph builds its Microsoft Graph API request URL by interpolating …

CVE-2026-54364