CVE-2026-97155 (CVSS 6.5)

Description

Fabasoft Folio Client before 2026, a locally installed component that communicates with the Fabasoft browser extension via web messaging, does not restrict which web origins may invoke its functions by default. The registry value VALIDDOMAINS, which limits permitted origins, was optional and empty by default, resulting in all domains being trusted. As a consequence, any website visited by a user with the Folio Client and browser extension installed could invoke client functions, e.g., related to downloading documents, opening documents, and synchronizing files. The first fixed builds are Fabasoft Folio Client 2026 (Build 26.0.0.10) and Fabasoft Folio Client 2026 April Release (Build 26.4.0.76). This client is, for example, shipped with Fabasoft eGov-Suite.

Is your site exposed to CVE-2026-97155?

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:R/S:U/C:N/I:H/A:N

EPSS — Exploit Prediction

0.0011

Probability of exploitation

0.01%

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-346 CWE-346

References

Other References

https://help.supportservices.fabasoft.com/index.php?topic=doc/Knowledge-Base/changes-to-fabasoft-folio-client-security-settings.htm

Frequently Asked Questions

What is CVE-2026-97155? +

Fabasoft Folio Client before 2026, a locally installed component that communicates with the Fabasoft browser extension via web messaging, does not restrict which web origins may invoke its functions by default. The registry value VALIDDOMAINS, which limits permitted origins, was optional and empty by default, resulting in all domains being trusted. As a consequence, any website visited by a user with the Folio Client and browser extension installed could invoke client functions, e.g., related to downloading documents, opening documents, and synchronizing files. The first fixed builds are Fabasoft Folio Client 2026 (Build 26.0.0.10) and Fabasoft Folio Client 2026 April Release (Build 26.4.0.76). This client is, for example, shipped with Fabasoft eGov-Suite. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2026-97155? +

CVE-2026-97155 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 0.0011, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-97155? +

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-2026-22077

OPPO Wallet APP contains a trusted domain validation flaw that allows attackers to bypass protected interface access restrictions, which may …

CVE-2026-45173

Idira Identity Browser Extension (Chrome, Firefox, and Edge builds) versions prior to 26.8.1 exhibit an origin validation flaw within its …

CVE-2025-3651

Improper Verification of Source of a Communication Channel in Work Desktop for Mac versions 10.8.1.46 and earlier allows attackers to …

CVE-2025-3462

"This issue is limited to motherboards and does not affect laptops, desktop computers, or other endpoints." An insufficient validation in …

CVE-2025-53399

In Sipwise rtpengine before 13.4.1.1, an origin-validation error in the endpoint-learning logic of the media-relay core allows remote attackers to …

CVE-2025-10193

DNS rebinding vulnerability in Neo4j Cypher MCP server allows malicious websites to bypass Same-Origin Policy protections and execute unauthorised tool …

CVE-2026-97155