VulnerabilityPublished 18 Mar 2026Updated 19 Mar 2026

CVE-2026-30048: Cross-site Scripting

Source CVE Database V5

Not known to be exploited · CVSS 5.4 Medium.

Data as of 26 Oct 2026, 13:47 UTC

CVSS 3.1 base score

5.4Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.2% chance of exploitation in 30 days – higher than 17% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: Required
Scope: Changed
Confidentiality: Low
Integrity: Low
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
Scope: Changed: An exploited vulnerability can affect resources beyond the security scope managed by the security authority of the vulnerable component. In this case, the vulnerable component and the impacted component are different and managed by different security authorities.
Confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the impacted component.
Integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 18 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

AI-suggested

To mitigate this vulnerability, organizations should implement strict input validation and output encoding on all user-supplied data before storage and rendering in the chat widget. Employing a robust Content Security Policy (CSP) can help limit the impact of injected scripts. Since no official patches are currently available, consider disabling or replacing the NotChatbot WebChat widget with a secure alternative that properly sanitizes inputs. Regularly audit and monitor chat logs for suspicious scripts or payloads. Educate developers and administrators about secure coding practices related to XSS prevention, including the use of well-maintained libraries for sanitization. Additionally, restrict privileges required to interact with the widget to minimize exploitation potential, and keep all related software components updated to the latest versions once patches are released. Implementing multi-factor authentication can reduce the impact of stolen credentials resulting from XSS attacks.

Description

CVE-2026-30048 is a stored cross-site scripting (XSS) vulnerability affecting the NotChatbot WebChat widget up to version 1.4.4. The vulnerability arises because user input is not properly sanitized before being stored and rendered in the chat conversation history, allowing attackers to inject arbitrary JavaScript code. This malicious code executes when the chat history is reloaded, potentially compromising users who view the chat. The issue is inherent to the widget itself and not dependent on specific website configurations. The vulnerability has a CVSS score of 5.4 (medium severity), requires low privileges and user interaction, and impacts confidentiality and integrity but not availability. No known exploits are currently reported in the wild. Organizations using this widget should prioritize input validation and consider patching or replacing the widget to mitigate risk.

Impact

The primary impact of this vulnerability is on the confidentiality and integrity of users interacting with the affected WebChat widget. An attacker can execute arbitrary JavaScript in the context of other users, potentially stealing sensitive information such as session cookies, personal data, or authentication tokens. This can lead to account compromise, unauthorized actions, or further exploitation within the affected web application. Since the vulnerability is stored XSS, the malicious code persists and affects all users who load the chat history, increasing the attack surface. Although availability is not directly impacted, the reputational damage and potential data breaches can have severe consequences for organizations. Enterprises relying on the NotChatbot widget for customer support or communication may face regulatory compliance issues if user data is compromised. The medium CVSS score reflects a moderate but non-trivial risk, especially in environments where the widget is widely deployed and trusted by users.

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #1OWASP Top 10 A05:2025: Injection (opens in a new tab)
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Implementation · Architecture and Design
Understand the context in which your data will be used and the encoding that will be expected. This is especially important when transmitting data between different components, or when generating outputs that can contain multiple encodings at the same time, such as web pages or multi-part mail messages.
Architecture and Design · Implementation · Attack Surface Reduction
Understand all the potential areas where untrusted inputs can enter your software: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide…
OWASP Cheat Sheets
Cross Site Scripting Prevention (opens in a new tab)
DOM based XSS Prevention (opens in a new tab)
Injection Prevention (opens in a new tab)
Abuse Case (opens in a new tab)
Deserialization (opens in a new tab)
OWASP ASVS 4.0.3
V5.3.3 (opens in a new tab)
V1.5.1 (opens in a new tab)
Attack patterns
XSS Using MIME Type Mismatch (opens in a new tab)
DOM-Based XSS (opens in a new tab)
Reflected XSS (opens in a new tab)
Stored XSS (opens in a new tab)
Cross-Site Scripting (XSS) (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 26 Mar 2026, 01:16 UTC

WeaknessesCWE-79

Technical details

References

Community reviews

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