Cyber Resilience

CVE-2026-5615

Medium

Published: 06 April 2026

Published
06 April 2026
Modified
27 April 2026
KEV Added
Patch
CVSS Score v4 5.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0146 81.3th percentile
Risk Priority 11 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-5615 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Feishu (inferred from references). Its CVSS base score is 5.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 18.7% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

A weakness has been identified in givanz Vvvebjs up to 2.0.5. The affected element is an unknown function of the file upload.php of the component File Upload Endpoint. This manipulation of the argument uploadAllowExtensions causes cross site scripting. Remote exploitation…

more

of the attack is possible. The exploit has been made available to the public and could be used for attacks. Patch name: 8cac22cff99b8bc701c408aa8e887fa702755336. Applying a patch is the recommended action to fix this issue. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

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.
Why these techniques?

XSS vulnerability in public-facing file upload endpoint (upload.php) directly enables remote exploitation of a web application.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

Affected Assets

Feishu
inferred from references and description; NVD did not file a CPE for this CVE

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79 CWE-94

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-94

Makes persistent code injection into loaded programs impossible when the executable image itself resides on hardware-protected read-only media.

addresses: CWE-94

Dynamically generated code can be produced and executed inside the isolated chamber, preventing host compromise from code-injection payloads.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

addresses: CWE-94

Directly prevents execution of attacker-supplied code written into data memory regions.

References