Misskey: Cross-site scripting in RSS feed item links
CVSS score
8.5
EPSS probability
%0.6
Risk score
0.1
Published
22 h ago
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Impact on My Inventory
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Vulnerability description
CVE AI research
DayBreach AI Explanation
Verified against sourcesSources read
1
Source agreement
Tam uyum
Evidence confidence
%55
Short explanation
A cross-site scripting vulnerability exists in Misskey due to RSS components failing to verify URL schemes of feed item links. This allows an attacker controlling feed content to provide an unsafe-scheme link that executes scripts when clicked.
This security flaw allows attackers to execute malicious scripts via RSS components upon user interaction, posing risks to confidentiality and integrity.
What should be done?
- Update software to version 2026.7.0 or later
- Follow vendor security advisories
Chain of evidence and sources
Misskey RSS bileşenleri, yapılandırılmış beslemelerden gelen öğe bağlantılarının URL şemalarını doğrulamamaktadır.
Eksik URL şeması doğrulaması, besleme içeriğini kontrol eden bir saldırganın güvensiz şema bağlantısı sağlamasına ve betik yürütülmesine izin verir.
Show the technical text from the sources
Misskey is an open source, federated social media platform. From 12.0.0 until 2026.7.0, the RSS components display feed item links from configured feeds without verifying their URL schemes. Missing URL scheme verification allows an attacker who controls feed content to provide an unsafe-scheme link that causes script execution when a user clicks it in an RSS widget. This issue is fixed in version 2026.7.0.
CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:N/SC:L/SI:L/SA:N
CWE: CWE-79
Explanation produced with the local gemini-flash-lite-latest model. Numerical metrics and the KEV, patch and exploit statuses are not determined by AI.
IMPACT: Affected Products and Software
Affected Products
The following products are affected by CVE-2026-104816 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.
| ID | VENDOR | PRODUCT | ACTION |
|---|---|---|---|
| 1 | misskey-dev | misskey | View |
RED HAT CSAF/VEX: Product Impact Check
SCORING: CVSS from Multiple Sources
CVSS Scores
The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.
| SCORE | VERSION | SEVERITY | VECTOR | SOURCE |
|---|---|---|---|---|
| 8.5 | CVSS V40 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:N/SC:L/SI:L/SA:N/E:X/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 | NVD |
| 8.5 | CVSS V4_0 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:N/SC:L/SI:L/SA:N | CVE CNA |
Patch and Remediation Guide
Solution & Remediation Advisory
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Public exploit and active exploitation status
Verified exploit intelligence
No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.
Weakness Classification and Attack Patterns (CWE & CAPEC)
CWE - Common Weakness Enumeration
While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-104816 is associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-104816 weaknesses.
Attack Vector and Accessibility
Official Sources and Advisories
CVSS Vector Radar Chart
8.5 / 10Vulnerability Scoring Details
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:N/SC:L/SI:L/SA:NYama durumu bilinmiyor
Weakness Type (CWE & CAPEC)
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