CVE-2026-22256VulnerabilityPublished 8 Jan 2026

CVE-2026-22256: salvo · Cross-site Scripting

Affects salvoSource CVE Database V5

Not known to be exploited · CVSS 8.8 High : upgrade to 0.88.1 soon.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 3.1 base score

8.8High

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

EPSS: 0.3% chance of exploitation in 30 days – higher than 26% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 0.88.1

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

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

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: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
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: 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: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 8 Jan 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 2026-10-26.

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 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 salvo and salvo-rs/salvo to 0.88.1.

Affected software

Product	Affected	Fixed in
salvo-rssalvo	Affected <0.88.1	Fixed in 0.88.1
crates.iosalvo-rs/salvo`pkg:cargo/salvo-rs/salvo`Other threats	Affected <0.88.1	Fixed in 0.88.1

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

AI-suggested

The primary mitigation is to upgrade all Salvo framework instances to version 0.88.1 or later, where the vulnerability is patched. Additionally, organizations should audit any custom HTML rendering code that inserts user-controlled input, ensuring proper output encoding and sanitization to prevent XSS. Implement Content Security Policy (CSP) headers to reduce the impact of potential XSS attacks. Web Application Firewalls (WAFs) can be configured to detect and block suspicious request patterns targeting path parameters. Regular security testing, including automated scanning and manual code reviews focusing on input handling, should be integrated into the development lifecycle. Finally, educate developers about secure coding practices related to input validation and output encoding in web applications.

Description

Salvo is a Rust web backend framework. Prior to version 0.88.1, the function list_html generate an file view of a folder which include a render of the current path, in which its inserted in the HTML without proper sanitation, this leads to reflected XSS using the fact that request path is decoded and normalized in the matching stage but not is inserted raw in the html view (current.path), the only constraint here is for the root path (eg. /files in the PoC example) to have a sub directory (e.g common ones styles/scripts/etc…) so that the matching return the list HTML page instead of the Not Found page. This issue has been patched in version 0.88.1.

Impact

For European organizations, this vulnerability can lead to the execution of arbitrary JavaScript in the context of affected web applications, potentially exposing sensitive user data such as session tokens, personal information, or enabling phishing attacks. The reflected XSS can also be leveraged to perform actions on behalf of authenticated users, leading to partial integrity compromise. Availability impact is low but possible through script-based attacks causing client-side disruptions. Organizations using Salvo in public-facing web services, especially those exposing directory listings or file views, are at risk. This can affect sectors like finance, healthcare, and government where web applications handle sensitive data. The vulnerability's ease of exploitation and high confidentiality impact make it a critical concern for maintaining trust and compliance with European data protection regulations such as GDPR.

Summary

CVE-2026-22256 is a reflected Cross-Site Scripting (XSS) vulnerability classified under CWE-79, found in the Salvo Rust web backend framework before version 0.88.1. The vulnerability exists in the list_html function, which generates an HTML view of a folder's contents. This function inserts the current request path into the HTML output without proper sanitization, allowing malicious input to be reflected in the response. The request path is decoded and normalized during routing but is inserted directly into the HTML view, enabling attackers to craft URLs that inject arbitrary JavaScript code. The vulnerability requires that the root path has a subdirectory to trigger the listing page instead of a 404 Not Found page. Exploitation is possible remotely without authentication but requires user interaction to visit the malicious URL. The CVSS v3.1 score is 8.8 (high), reflecting network attack vector, low attack complexity, no privileges required, user interaction required, and a scope change with high confidentiality impact, limited integrity impact, and low availability impact. Although no known exploits are reported in the wild yet, the vulnerability poses a significant risk for web applications using affected Salvo versions. The issue has been fixed in version 0.88.1 by properly sanitizing the path input before rendering it in HTML.

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 8 Jan 2026, 19:08 UTC

WeaknessesCWE-79

Technical details

References

Community reviews

Related threats