Cyber Resilience

CVE-2026-26724

XSS in Keystorage Global Facilities Management Software 20230721a

Public PoCXSS
Published
20 February 2026
Modified
26 February 2026
CVSS Score v3.1 7.6
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:L/A:N
EPSS Score 0.0028 20th percentile
Risk Priority 52 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-26724 is a high-severity Cross-site Scripting (CWE-79) vulnerability in Keystorage Global Facilities Management Software. Its CVSS base score is 7.6 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Browser Session Hijacking (T1185); ranked at the 20th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-26724 is a Cross-Site Scripting (XSS) vulnerability, classified under CWE-79, affecting Key Systems Inc Global Facilities Management Software version 20230721a. The flaw enables a remote attacker to execute arbitrary code through the selectgroup and gn parameters on the /?Function=Groups endpoint. It carries a CVSS v3.1 base score of 7.6, reflecting network accessibility, low attack complexity, requirement for low privileges and user interaction, changed scope, high confidentiality impact, low integrity impact, and no availability impact.

An attacker with low privileges (PR:L) can exploit this vulnerability remotely over the network by crafting malicious inputs for the vulnerable parameters and inducing a targeted user to interact with them, such as by clicking a link or submitting a form (UI:R). Successful exploitation allows execution of arbitrary code in the victim's browser context, potentially compromising sensitive data due to the high confidentiality impact and scope change.

Mitigation details are available in the vulnerability disclosure at https://github.com/chndlrx/vulnerability-disclosures/tree/main/CVE-2026-26724, published on 2026-02-20.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Cross Site Scripting vulnerability in Key Systems Inc Global Facilities Management Software v. 20230721a allows a remote attacker to execute arbitrary code via the selectgroup and gn parameters on the /?Function=Groups endpoint.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1185 Browser Session Hijacking Collection
Adversaries may take advantage of security vulnerabilities and inherent functionality in browser software to change content, modify user-behaviors, and intercept information as part of various browser session hijacking techniques.
T1539 Steal Web Session Cookie Credential Access
An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials.
T1659 Content Injection Initial Access
Adversaries may gain access and continuously communicate with victims by injecting malicious content into systems through online network traffic.
T1189 Drive-by Compromise Initial Access
Adversaries may gain access to a system through a user visiting a website over the normal course of browsing.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-41136Shared CWE-79
CVE-2023-2768Shared CWE-79
CVE-2023-38476Shared CWE-79
CVE-2023-5026Shared CWE-79
CVE-2023-27225Shared CWE-79
CVE-2023-37132Shared CWE-79
CVE-2023-0514Shared CWE-79
CVE-2023-28774Shared CWE-79
CVE-2023-3074Shared CWE-79
CVE-2023-3539Shared CWE-79

Affected Assets

keystorage
global facilities management software
20230721a

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.1.2
  • V1.3.2

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation can discover missing or incorrect input neutralization through targeted web-application tests.

Input validation directly enforces neutralization of untrusted data before it reaches web output generation.

Output filtering can catch or sanitize unneutralized script content before it is served to users.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly target introduction of XSS via coding standards/testing (mostly), yet the single broad outcome leaves many specific neutralization vectors unaddressed (partial).

PR.PS-02 partial match
prevents

Patching and EOL replacement can remediate known XSS instances in libraries or frameworks (partial) but do nothing to enforce input neutralization in application code (none).

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Secure-coding testing and automated code-analysis tools are applied to detect improper neutralization of script-related content during web-page generation.

prevents

Knowledge exchange on emerging attack techniques and patches reduces the likelihood that cross-site scripting flaws remain unaddressed in deployed applications.

prevents

Operational indicators of compromise for web-application attacks can be incorporated into WAF or input-filtering rules, lowering the likelihood that unsanitized data reaches the browser.

prevents

Requiring language-specific secure-coding standards and automated scanning during the SDLC catches missing output encoding or improper neutralization of untrusted data before the software reaches production.

prevents

Secure-coding standards, SAST scans and removal of insecure code samples together eliminate the failure to neutralize script content that produces cross-site scripting flaws.

References