ghsa-2j42-h78h-q4fg
Vulnerability from github
Summary
A Cross-Site Scripting (XSS) vulnerability exists in Beego's RenderForm() function due to improper HTML escaping of user-controlled data. This vulnerability allows attackers to inject malicious JavaScript code that executes in victims' browsers, potentially leading to session hijacking, credential theft, or account takeover. The vulnerability affects any application using Beego's RenderForm() function with user-provided data. Since it is a high-level function generating an entire form markup, many developers would assume it automatically escapes attributes (the way most frameworks do).
Details
The vulnerability is located in the renderFormField() function in Beego's templatefunc.go file (around lines 316-356). This function directly injects user-provided values into HTML without proper escaping:
go
return fmt.Sprintf(`%v<input%v%v name="%v" type="%v" value="%v"%v>`,
label, id, class, name, fType, value, requiredString)
None of the values (label, id, class, name, value) are properly HTML-escaped before being inserted into the HTML template. This allows attackers to break out of the attribute context or inject HTML tags directly. The vulnerability can be exploited in two main ways:
- Attribute Injection: By injecting code into fields like DisplayName, an attacker can break out of the attribute context and execute JavaScript.
- Content Injection: By injecting HTML tags into textarea content, an attacker can execute JavaScript.
The RenderForm() function returns template.HTML, which bypasses Go's automatic HTML escaping, making this vulnerability particularly dangerous.
PoC
Retrieve the following (secret) gist: https://gist.github.com/thevilledev/8fd0cab3f098320aa9daab04be59fd2b
To run it:
go
go mod init beego-xss-poc
go mod tidy
go run poc.go
Open your browser and navigate to http://localhost:8080/
The application demonstrates the vulnerability through several examples:
- /profile - Shows a profile with malicious data in the Display Name and Bio fields
- /admin - Shows multiple user profiles, including one with malicious data
- /submit - Allows you to create your own profile with malicious data
In addition, you may use this Go test in templatefunc_test.go. The test passes, validating the vulnerability.
``go
func TestRenderFormXSSVulnerability(t *testing.T) {
type UserProfile struct {
DisplayName stringform:"displayName,text,Name:"Bio stringform:",textarea"`
}
// Test case 1: Attribute injection in input field
maliciousUser := UserProfile{
DisplayName: `" onmouseover="alert('XSS')" data-malicious="`,
Bio: "Normal bio text",
}
output := RenderForm(&maliciousUser)
// The vulnerable output would contain the unescaped JavaScript
if !strings.Contains(string(output), `onmouseover="alert('XSS')"`) {
t.Errorf("Expected XSS vulnerability in attribute, but got safe output: %v", output)
}
// Test case 2: Script injection in textarea
maliciousUser2 := UserProfile{
DisplayName: "Normal Name",
Bio: `</textarea><script>alert('XSS')</script><textarea>`,
}
output = RenderForm(&maliciousUser2)
// The vulnerable output would contain the unescaped script tag
if !strings.Contains(string(output), `</textarea><script>alert('XSS')`) {
t.Errorf("Expected XSS vulnerability in textarea content, but got safe output: %v", output)
}
} ```
Impact
This is a high-severity vulnerability with the following impacts:
- Cross-Site Scripting (XSS): Allows execution of arbitrary JavaScript in the context of the victim's browser.
- Session Hijacking: Attackers can steal session cookies and impersonate victims.
- Credential Theft: Attackers can create fake login forms to steal credentials.
- Account Takeover: Attackers can perform actions on behalf of the victim.
- Data Exfiltration: Sensitive data visible in the browser can be stolen.
This is particularly concerning in admin panels or user management interfaces where one user's data is displayed to another user (typically an administrator).
Mitigation
The vulnerability can be fixed by properly escaping all user-provided values before inserting them into HTML, for example:
```go // Convert value to string and escape it valueStr := "" if value != nil { valueStr = template.HTMLEscapeString(fmt.Sprintf("%v", value)) }
// Escape the name and label escapedName := template.HTMLEscapeString(name) escapedLabel := template.HTMLEscapeString(label) escapedType := template.HTMLEscapeString(fType)
return fmt.Sprintf(%v<input%v%v name="%v" type="%v" value="%v"%v>,
escapedLabel, id, class, escapedName, escapedType, valueStr, requiredString)
```
{
"affected": [
{
"package": {
"ecosystem": "Go",
"name": "github.com/beego/beego/v2"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2.3.6"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Go",
"name": "github.com/beego/beego"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "1.12.14"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2025-30223"
],
"database_specific": {
"cwe_ids": [
"CWE-79"
],
"github_reviewed": true,
"github_reviewed_at": "2025-03-31T16:55:22Z",
"nvd_published_at": "2025-03-31T17:15:42Z",
"severity": "CRITICAL"
},
"details": "### Summary\n\nA Cross-Site Scripting (XSS) vulnerability exists in Beego\u0027s `RenderForm()` function due to improper HTML escaping of user-controlled data. This vulnerability allows attackers to inject malicious JavaScript code that executes in victims\u0027 browsers, potentially leading to session hijacking, credential theft, or account takeover. The vulnerability affects any application using Beego\u0027s `RenderForm()` function with user-provided data. Since it is a high-level function generating an entire form markup, many developers would assume it automatically escapes attributes (the way most frameworks do).\n\n### Details\n\nThe vulnerability is located in the `renderFormField()` function in Beego\u0027s `templatefunc.go` file (around lines 316-356). This function directly injects user-provided values into HTML without proper escaping:\n\n```go\nreturn fmt.Sprintf(`%v\u003cinput%v%v name=\"%v\" type=\"%v\" value=\"%v\"%v\u003e`, \n label, id, class, name, fType, value, requiredString)\n```\n\nNone of the values (label, id, class, name, value) are properly HTML-escaped before being inserted into the HTML template. This allows attackers to break out of the attribute context or inject HTML tags directly.\nThe vulnerability can be exploited in two main ways:\n\n- Attribute Injection: By injecting code into fields like DisplayName, an attacker can break out of the attribute context and execute JavaScript.\n- Content Injection: By injecting HTML tags into textarea content, an attacker can execute JavaScript.\n\nThe `RenderForm()` function returns `template.HTML`, which bypasses Go\u0027s automatic HTML escaping, making this vulnerability particularly dangerous.\n\n### PoC\n\nRetrieve the following (secret) gist: https://gist.github.com/thevilledev/8fd0cab3f098320aa9daab04be59fd2b\n\nTo run it:\n\n```go\ngo mod init beego-xss-poc\ngo mod tidy\ngo run poc.go\n```\n\nOpen your browser and navigate to http://localhost:8080/\n\nThe application demonstrates the vulnerability through several examples:\n- `/profile` - Shows a profile with malicious data in the Display Name and Bio fields\n- `/admin` - Shows multiple user profiles, including one with malicious data\n- `/submit` - Allows you to create your own profile with malicious data\n\nIn addition, you may use this Go test in `templatefunc_test.go`. The test passes, validating the vulnerability.\n\n```go\nfunc TestRenderFormXSSVulnerability(t *testing.T) {\n\ttype UserProfile struct {\n\t\tDisplayName string `form:\"displayName,text,Name:\"`\n\t\tBio string `form:\",textarea\"`\n\t}\n\n\t// Test case 1: Attribute injection in input field\n\tmaliciousUser := UserProfile{\n\t\tDisplayName: `\" onmouseover=\"alert(\u0027XSS\u0027)\" data-malicious=\"`,\n\t\tBio: \"Normal bio text\",\n\t}\n\n\toutput := RenderForm(\u0026maliciousUser)\n\n\t// The vulnerable output would contain the unescaped JavaScript\n\tif !strings.Contains(string(output), `onmouseover=\"alert(\u0027XSS\u0027)\"`) {\n\t\tt.Errorf(\"Expected XSS vulnerability in attribute, but got safe output: %v\", output)\n\t}\n\n\t// Test case 2: Script injection in textarea\n\tmaliciousUser2 := UserProfile{\n\t\tDisplayName: \"Normal Name\",\n\t\tBio: `\u003c/textarea\u003e\u003cscript\u003ealert(\u0027XSS\u0027)\u003c/script\u003e\u003ctextarea\u003e`,\n\t}\n\n\toutput = RenderForm(\u0026maliciousUser2)\n\n\t// The vulnerable output would contain the unescaped script tag\n\tif !strings.Contains(string(output), `\u003c/textarea\u003e\u003cscript\u003ealert(\u0027XSS\u0027)`) {\n\t\tt.Errorf(\"Expected XSS vulnerability in textarea content, but got safe output: %v\", output)\n\t}\n}\n```\n\n### Impact\n\nThis is a high-severity vulnerability with the following impacts:\n\n- Cross-Site Scripting (XSS): Allows execution of arbitrary JavaScript in the context of the victim\u0027s browser.\n- Session Hijacking: Attackers can steal session cookies and impersonate victims.\n- Credential Theft: Attackers can create fake login forms to steal credentials.\n- Account Takeover: Attackers can perform actions on behalf of the victim.\n- Data Exfiltration: Sensitive data visible in the browser can be stolen.\n\nThis is particularly concerning in admin panels or user management interfaces where one user\u0027s data is displayed to another user (typically an administrator).\n\n### Mitigation\n\nThe vulnerability can be fixed by properly escaping all user-provided values before inserting them into HTML, for example:\n\n```go\n// Convert value to string and escape it\nvalueStr := \"\"\nif value != nil {\n valueStr = template.HTMLEscapeString(fmt.Sprintf(\"%v\", value))\n}\n\n// Escape the name and label\nescapedName := template.HTMLEscapeString(name)\nescapedLabel := template.HTMLEscapeString(label)\nescapedType := template.HTMLEscapeString(fType)\n\nreturn fmt.Sprintf(`%v\u003cinput%v%v name=\"%v\" type=\"%v\" value=\"%v\"%v\u003e`, \n escapedLabel, id, class, escapedName, escapedType, valueStr, requiredString)\n```",
"id": "GHSA-2j42-h78h-q4fg",
"modified": "2025-08-04T15:12:27Z",
"published": "2025-03-31T16:55:22Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/beego/beego/security/advisories/GHSA-2j42-h78h-q4fg"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-30223"
},
{
"type": "WEB",
"url": "https://github.com/beego/beego/commit/939bb18c66406466715ddadd25dd9ffa6f169e25"
},
{
"type": "PACKAGE",
"url": "https://github.com/beego/beego"
},
{
"type": "WEB",
"url": "https://pkg.go.dev/vuln/GO-2025-3585"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N",
"type": "CVSS_V3"
}
],
"summary": "Beego allows Reflected/Stored XSS in Beego\u0027s RenderForm() Function Due to Unescaped User Input"
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.