VulnerabilityPublished 13 Jul 2026

CVE-2026-49259: NukeViet · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Affects nukeviet/nukevietSource GCVE Database

Compare

Not known to be exploited · CVSS 8.7 High : upgrade to 4.6.00 soon.

Data as of 14 Jul 2026, 10:00 UTC

CVSS 3.1 base score

8.7High

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

Patch: Available – fixed in 4.6.00

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: Required
Scope: Changed
Confidentiality: High
Integrity: High
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: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to 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 13 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 29 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.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), 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

Upgrade nukeviet/nukeviet to 4.6.00.

Affected software

Product	Affected	Fixed in
Packagistnukeviet/nukeviet	Affected <4.6.00	Fixed in 4.6.00

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

The preferred remediation is to remove the vulnerable post_name parameter from the inline onclick handler and instead retrieve the display name from the DOM within the JavaScript function. Alternatively, if passing the value inline is necessary, it must be properly escaped using JSON encoding (e.g., json_encode in PHP) to ensure safe JavaScript string literals. Relying on HTML numeric character references for JavaScript escaping is insufficient. Users should audit other code locations for similar unsafe patterns.

Description

NukeViet CMS versions prior to 4.6.00 contain a stored cross-site scripting (XSS) vulnerability. A low-privileged authenticated user can inject JavaScript payloads into their profile's display name fields, which execute in the browsers of visitors who click the Reply link on that user's comment. The vulnerability arises from improper escaping of user input placed inside a JavaScript string literal within an HTML attribute, allowing execution of arbitrary scripts. This can lead to privilege escalation, credential phishing, and data exfiltration. The vulnerability affects the comment template's inline onclick handler and is exploitable under default configurations without CAPTCHA or moderation.

Impact

An attacker with a regular user account can execute arbitrary JavaScript in the browsers of any visitors who interact with the Reply button on their comment, including administrators. This can lead to privilege escalation by hijacking admin sessions, forging administrative actions, credential phishing through fake login forms, and exfiltration of page content and non-HttpOnly cookies. Although session cookies are HttpOnly and not directly accessible, the attack remains capable of causing significant harm through other vectors.

Summary

A stored XSS vulnerability exists in NukeViet CMS versions <4.6.00 due to improper neutralization of user input in JavaScript string literals embedded in HTML attributes. The first_name and last_name profile fields are sanitized with HTML numeric character references, which are decoded by browsers before JavaScript parsing, allowing an attacker to break out of the string context and execute arbitrary JavaScript. This occurs in the {COMMENT.post_name} variable used inside an inline onclick handler in the comment template. An attacker with a low-privileged account can inject a payload into their profile name fields and post a comment, causing the payload to execute in any visitor's browser who clicks the Reply link on that comment. The vulnerability enables actions such as admin session hijacking, phishing, and data exfiltration. The recommended fix is to remove the vulnerable inline handler or use proper JSON encoding for the input.

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

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 14 Jul 2026, 10:00 UTC

WeaknessesCWE-79

Technical details

References

Community reviews

Related threats