Notes
CVE-2023-39955
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization Output encoding, context-aware escaping
MITRE ATT&CK
2 techniques across 2 tactics: Initial Access, Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 6.1 (MEDIUM). Attack characteristics: network attack vector, low complexity, no privileges required, user interaction required. |
| Exploit ScenarioDerived | A remote attacker could inject malicious scripts into web pages viewed by other users by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
Notes is a note-taking app for Nextcloud, an open-source cloud platform. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Cross-Site Scripting (XSS) vulnerability could allow attackers to inject malicious scripts into web pages viewed by other users.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Sanitize all user input, use Content-Security-Policy headers, encode output contextually (HTML, JS, URL). Use frameworks with built-in XSS protection.
Affects your stack
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Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Cross-Site Scripting (XSS) (CWE-79), which allows attackers to inject malicious scripts into web pages viewed by other users. Notes is a note-taking app for Nextcloud, an open-source cloud platform. Starting in version 4.4.0 and prior to version 4.8.0, when creating a note file with HTML, the content is rendered in the preview instead of the file being offered to download. Nextcloud Notes app version 4.8.0 contains a patch for the issue. No known workarounds are available. Affected products include: Nextcloud Notes. Version information: version 4.4.0.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
Notes is a note-taking app for Nextcloud, an open-source cloud platform. Starting in version 4.4.0 and prior to version 4.8.0, when creating a note file with HTML, the content is rendered in the preview instead of the file being offered to download. Nextcloud Notes app version 4.8.0 contains a patch for the issue. No known workarounds are available.
Threat Intelligence Overview
NVD
CVE.org
EPSS
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Cross-Site Scripting occurs when an application accepts untrusted data and sends it to a web browser without proper validation or encoding.
Affected Products (CPE)NVD
Stack-based out-of-bounds write in Samsung Notes prior to version 4.4.21.62 allows remote attackers to execute arbitrary
A vulnerability in the MIME message handling of the HCL Notes v9 client could potentially be exploited by an unauthentic
A vulnerability in the MIME message handling of the Notes client (versions 9 and 10) could potentially be exploited by a
A vulnerability in the input parameter handling of HCL Notes v9 could potentially be exploited by an authenticated attac
Heap-based out-of-bounds write in Samsung Notes prior to version 4.4.21.62 allows local attackers to execute arbitrary c
Path traversal in Samsung Notes prior to version 4.4.21.62 allows local attackers to execute arbitrary code. Rated high
Out-of-bounds write in applying connected information in Samsung Notes prior to version 4.4.21.62 allows local attackers
Out-of-bounds write in appending paragraph in Samsung Notes prior to version 4.4.21.62 allows local attackers to potenti
HCL Notes is susceptible to a stack based buffer overflow vulnerability in lasr.dll in Micro Focus KeyView. Rated high s
HCL Notes is susceptible to a stack based buffer overflow vulnerability in wp6sr.dll in Micro Focus KeyView. Rated high
HCL Notes is susceptible to a stack based buffer overflow vulnerability in lasr.dll in Micro Focus KeyView. Rated high s
A possible buffer overflow vulnerability in maetd_eco_cb_mode of libSPenBase library of Samsung Notes prior to Samsung N
Exploit-DB