{
"document": {
"category": "csaf_base",
"csaf_version": "2.0",
"distribution": {
"tlp": {
"label": "WHITE"
}
},
"lang": "en",
"notes": [
{
"category": "legal_disclaimer",
"text": "The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this portal to enhance access to its information and vulnerabilities. The use of this information is subject to the following terms and conditions:\n\nThe vulnerabilities disclosed in this portal are gathered by NCSC-NL from a variety of open sources, which the user can retrieve from other platforms. NCSC-NL makes every reasonable effort to ensure that the content of this portal is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or real-time keeping up-to-date. NCSC-NL does not control nor guarantee the accuracy, relevance, timeliness or completeness of information obtained from these external sources. The vulnerabilities disclosed in this portal are intended solely for the convenience of professional parties to take appropriate measures to manage the risks posed to the cybersecurity. No rights can be derived from the information provided therein.\n\nNCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of the vulnerabilities disclosed in this portal. This includes damage resulting from the inaccuracy of incompleteness of the information contained in it.\nThe information on this page is subject to Dutch law. All disputes related to or arising from the use of this portal regarding the disclosure of vulnerabilities will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings."
}
],
"publisher": {
"category": "coordinator",
"contact_details": "cert@ncsc.nl",
"name": "National Cyber Security Centre",
"namespace": "https://www.ncsc.nl/"
},
"title": "CVE-2026-33683",
"tracking": {
"current_release_date": "2026-03-26T00:49:34.965438Z",
"generator": {
"date": "2026-02-17T15:00:00Z",
"engine": {
"name": "V.E.L.M.A",
"version": "1.7"
}
},
"id": "CVE-2026-33683",
"initial_release_date": "2026-03-24T13:51:40.518585Z",
"revision_history": [
{
"date": "2026-03-24T13:51:40.518585Z",
"number": "1",
"summary": "CVE created.| Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (2).| CWES updated (1)."
},
{
"date": "2026-03-24T13:51:42.174516Z",
"number": "2",
"summary": "NCSC Score created."
},
{
"date": "2026-03-24T14:25:37.840138Z",
"number": "3",
"summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (1).| References created (2).| CWES updated (1)."
},
{
"date": "2026-03-24T14:25:40.993153Z",
"number": "4",
"summary": "NCSC Score updated."
},
{
"date": "2026-03-24T21:37:17.821902Z",
"number": "5",
"summary": "Source connected.| CVE status created. (valid)| EPSS created."
},
{
"date": "2026-03-24T21:37:32.741126Z",
"number": "6",
"summary": "NCSC Score updated."
},
{
"date": "2026-03-25T15:39:28.587917Z",
"number": "7",
"summary": "Unknown change."
},
{
"date": "2026-03-25T15:39:30.117153Z",
"number": "8",
"summary": "NCSC Score updated."
},
{
"date": "2026-03-25T18:26:48.990428Z",
"number": "9",
"summary": "Products connected (1).| Product Identifiers created (1).| Exploits created (1)."
},
{
"date": "2026-03-25T18:26:58.071906Z",
"number": "10",
"summary": "NCSC Score updated."
},
{
"date": "2026-03-25T20:59:56.139284Z",
"number": "11",
"summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (4).| CWES updated (1)."
},
{
"date": "2026-03-25T20:59:58.182983Z",
"number": "12",
"summary": "NCSC Score updated."
},
{
"date": "2026-03-26T00:48:51.272171Z",
"number": "13",
"summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (18).| Product Identifiers created (17).| References created (3).| CWES updated (1)."
}
],
"status": "interim",
"version": "13"
}
},
"product_tree": {
"branches": [
{
"branches": [
{
"branches": [
{
"category": "product_version_range",
"name": "vers:unknown/<=26.0",
"product": {
"name": "vers:unknown/<=26.0",
"product_id": "CSAFPID-5893889",
"product_identification_helper": {
"cpe": "cpe:2.3:a:wwbn:avideo:*:*:*:*:*:*:*:*"
}
}
}
],
"category": "product_name",
"name": "AVideo"
},
{
"branches": [
{
"category": "product_version_range",
"name": "vers:unknown/10.4",
"product": {
"name": "vers:unknown/10.4",
"product_id": "CSAFPID-5656122",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@10.4"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/10.8",
"product": {
"name": "vers:unknown/10.8",
"product_id": "CSAFPID-5656123",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@10.8"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/11",
"product": {
"name": "vers:unknown/11",
"product_id": "CSAFPID-5656124",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@11"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/11.1",
"product": {
"name": "vers:unknown/11.1",
"product_id": "CSAFPID-5656125",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@11.1"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/11.1.1",
"product": {
"name": "vers:unknown/11.1.1",
"product_id": "CSAFPID-5656126",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@11.1.1"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/11.5",
"product": {
"name": "vers:unknown/11.5",
"product_id": "CSAFPID-5656127",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@11.5"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/11.6",
"product": {
"name": "vers:unknown/11.6",
"product_id": "CSAFPID-5656128",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@11.6"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/12.4",
"product": {
"name": "vers:unknown/12.4",
"product_id": "CSAFPID-5656129",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@12.4"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/14.3",
"product": {
"name": "vers:unknown/14.3",
"product_id": "CSAFPID-5656130",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@14.3"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/14.3.1",
"product": {
"name": "vers:unknown/14.3.1",
"product_id": "CSAFPID-5656131",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@14.3.1"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/14.4",
"product": {
"name": "vers:unknown/14.4",
"product_id": "CSAFPID-5656132",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@14.4"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/18.0",
"product": {
"name": "vers:unknown/18.0",
"product_id": "CSAFPID-5656133",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@18.0"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/21.0",
"product": {
"name": "vers:unknown/21.0",
"product_id": "CSAFPID-5721197",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@21.0"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/22.0",
"product": {
"name": "vers:unknown/22.0",
"product_id": "CSAFPID-5772271",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@22.0"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/24.0",
"product": {
"name": "vers:unknown/24.0",
"product_id": "CSAFPID-5772272",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@24.0"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/25.0",
"product": {
"name": "vers:unknown/25.0",
"product_id": "CSAFPID-5840723",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@25.0"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/26.0",
"product": {
"name": "vers:unknown/26.0",
"product_id": "CSAFPID-5878928",
"product_identification_helper": {
"purl": "pkg:composer/wwbn/avideo@26.0"
}
}
},
{
"category": "product_version_range",
"name": "vers:unknown/>=0|<=26.0",
"product": {
"name": "vers:unknown/>=0|<=26.0",
"product_id": "CSAFPID-5878929"
}
}
],
"category": "product_name",
"name": "avideo"
}
],
"category": "vendor",
"name": "WWBN"
}
]
},
"vulnerabilities": [
{
"cve": "CVE-2026-33683",
"cwe": {
"id": "CWE-79",
"name": "Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')"
},
"notes": [
{
"category": "description",
"text": "WWBN AVideo is an open source video platform. In versions up to and including 26.0, a sanitization order-of-operations flaw in the user profile \"about\" field allows any registered user to inject arbitrary JavaScript that executes when other users visit their channel page. The `xss_esc()` function entity-encodes input before `strip_specific_tags()` can match dangerous HTML tags, and `html_entity_decode()` on output reverses the encoding, restoring the raw malicious HTML. Commit 7cfdc380dae1e56bbb5de581470d9e9957445df0 contains a patch.",
"title": "nvd - https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-33683"
},
{
"category": "description",
"text": "WWBN AVideo is an open source video platform. In versions up to and including 26.0, a sanitization order-of-operations flaw in the user profile \"about\" field allows any registered user to inject arbitrary JavaScript that executes when other users visit their channel page. The `xss_esc()` function entity-encodes input before `strip_specific_tags()` can match dangerous HTML tags, and `html_entity_decode()` on output reverses the encoding, restoring the raw malicious HTML. Commit 7cfdc380dae1e56bbb5de581470d9e9957445df0 contains a patch.",
"title": "cveprojectv5 - https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/33xxx/CVE-2026-33683.json"
},
{
"category": "description",
"text": "## Summary\n\nA sanitization order-of-operations flaw in the user profile \"about\" field allows any registered user to inject arbitrary JavaScript that executes when other users visit their channel page. The `xss_esc()` function entity-encodes input before `strip_specific_tags()` can match dangerous HTML tags, and `html_entity_decode()` on output reverses the encoding, restoring the raw malicious HTML.\n\n## Details\n\n**Input sanitization** in `objects/user.php:156`:\n\n```php\npublic function setAbout($about)\n{\n $this->about = strip_specific_tags(xss_esc($about));\n}\n```\n\nThe call order is `strip_specific_tags(xss_esc($about))`. The inner `xss_esc()` function (`objects/functionsSecurity.php:233`) calls `htmlspecialchars()`:\n\n```php\n$result = @htmlspecialchars($text, ENT_QUOTES, 'UTF-8');\n```\n\nThis encodes `` to `<script>alert(1)</script>`.\n\nThen `strip_specific_tags()` (`objects/functions.php:6623-6636`) runs regex patterns to remove dangerous tags:\n\n```php\n$string = preg_replace('/<' . $tag . '[^>]*>(.*?)<\\/' . $tag . '>/s', $replacement, $string);\n```\n\nBut the regex looks for literal `&user=attacker&pass=password123&email=attacker@example.com&name=Attacker&analyticsCode=&donationLink=&phone='\n```\n\n## Impact\n\n- **Session hijacking:** Attacker can steal session cookies of any user (including administrators) who visits their channel page\n- **Account takeover:** Stolen admin session tokens allow full administrative access to the AVideo instance\n- **Phishing:** Attacker can inject fake login forms or redirect users to malicious sites\n- **Worm potential:** Stored XSS could modify other users' profiles programmatically, creating a self-propagating worm\n\nThis is a stored XSS affecting all visitors to any attacker-controlled channel page, with no user interaction beyond navigating to the page.\n\n## Recommended Fix\n\n**Option 1 (Recommended — remove html_entity_decode):** The entity-encoded string is already safe for display. Remove the decode call in `view/channelBody.php`:\n\n```php\n// Before (VULNERABLE):\n$about = html_entity_decode($user->getAbout());\n\n// After (FIXED):\n$about = $user->getAbout();\n```\n\n**Option 2 (If rich HTML is intended):** Reverse the sanitization order in `objects/user.php:156` and use a proper sanitizer:\n\n```php\n// Before (VULNERABLE):\n$this->about = strip_specific_tags(xss_esc($about));\n\n// After (FIXED — strip tags on raw HTML first, then encode):\n$this->about = xss_esc(strip_specific_tags($about));\n```\n\n**Option 3 (Best — if rich HTML in about is desired):** Replace both `strip_specific_tags()` and `xss_esc()` with HTMLPurifier, which properly handles allowlisted HTML sanitization:\n\n```php\nrequire_once 'vendor/ezyang/htmlpurifier/library/HTMLPurifier.auto.php';\n$config = HTMLPurifier_Config::createDefault();\n$config->set('HTML.Allowed', 'p,br,b,i,u,a[href],ul,ol,li,strong,em');\n$purifier = new HTMLPurifier($config);\n$this->about = $purifier->purify($about);\n```\n\nAnd on output, remove `html_entity_decode()` — output the purified HTML directly.",
"title": "github - https://api.github.com/advisories/GHSA-ghx5-7jjg-q2j7"
},
{
"category": "description",
"text": "## Summary\n\nA sanitization order-of-operations flaw in the user profile \"about\" field allows any registered user to inject arbitrary JavaScript that executes when other users visit their channel page. The `xss_esc()` function entity-encodes input before `strip_specific_tags()` can match dangerous HTML tags, and `html_entity_decode()` on output reverses the encoding, restoring the raw malicious HTML.\n\n## Details\n\n**Input sanitization** in `objects/user.php:156`:\n\n```php\npublic function setAbout($about)\n{\n $this->about = strip_specific_tags(xss_esc($about));\n}\n```\n\nThe call order is `strip_specific_tags(xss_esc($about))`. The inner `xss_esc()` function (`objects/functionsSecurity.php:233`) calls `htmlspecialchars()`:\n\n```php\n$result = @htmlspecialchars($text, ENT_QUOTES, 'UTF-8');\n```\n\nThis encodes `` to `<script>alert(1)</script>`.\n\nThen `strip_specific_tags()` (`objects/functions.php:6623-6636`) runs regex patterns to remove dangerous tags:\n\n```php\n$string = preg_replace('/<' . $tag . '[^>]*>(.*?)<\\/' . $tag . '>/s', $replacement, $string);\n```\n\nBut the regex looks for literal `&user=attacker&pass=password123&email=attacker@example.com&name=Attacker&analyticsCode=&donationLink=&phone='\n```\n\n## Impact\n\n- **Session hijacking:** Attacker can steal session cookies of any user (including administrators) who visits their channel page\n- **Account takeover:** Stolen admin session tokens allow full administrative access to the AVideo instance\n- **Phishing:** Attacker can inject fake login forms or redirect users to malicious sites\n- **Worm potential:** Stored XSS could modify other users' profiles programmatically, creating a self-propagating worm\n\nThis is a stored XSS affecting all visitors to any attacker-controlled channel page, with no user interaction beyond navigating to the page.\n\n## Recommended Fix\n\n**Option 1 (Recommended — remove html_entity_decode):** The entity-encoded string is already safe for display. Remove the decode call in `view/channelBody.php`:\n\n```php\n// Before (VULNERABLE):\n$about = html_entity_decode($user->getAbout());\n\n// After (FIXED):\n$about = $user->getAbout();\n```\n\n**Option 2 (If rich HTML is intended):** Reverse the sanitization order in `objects/user.php:156` and use a proper sanitizer:\n\n```php\n// Before (VULNERABLE):\n$this->about = strip_specific_tags(xss_esc($about));\n\n// After (FIXED — strip tags on raw HTML first, then encode):\n$this->about = xss_esc(strip_specific_tags($about));\n```\n\n**Option 3 (Best — if rich HTML in about is desired):** Replace both `strip_specific_tags()` and `xss_esc()` with HTMLPurifier, which properly handles allowlisted HTML sanitization:\n\n```php\nrequire_once 'vendor/ezyang/htmlpurifier/library/HTMLPurifier.auto.php';\n$config = HTMLPurifier_Config::createDefault();\n$config->set('HTML.Allowed', 'p,br,b,i,u,a[href],ul,ol,li,strong,em');\n$purifier = new HTMLPurifier($config);\n$this->about = $purifier->purify($about);\n```\n\nAnd on output, remove `html_entity_decode()` — output the purified HTML directly.",
"title": "osv - https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/Packagist%2FGHSA-ghx5-7jjg-q2j7.json?alt=media"
},
{
"category": "other",
"text": "0.00029",
"title": "EPSS"
},
{
"category": "other",
"text": "4.0",
"title": "NCSC Score"
},
{
"category": "other",
"text": "There is cwe data available from source Github",
"title": "NCSC Score top increasing factors"
},
{
"category": "other",
"text": "Is related to (a version of) an uncommon product, There is exploit data available from source Nvd",
"title": "NCSC Score top decreasing factors"
}
],
"product_status": {
"known_affected": [
"CSAFPID-5893889",
"CSAFPID-5656122",
"CSAFPID-5656123",
"CSAFPID-5656124",
"CSAFPID-5656125",
"CSAFPID-5656126",
"CSAFPID-5656127",
"CSAFPID-5656128",
"CSAFPID-5656129",
"CSAFPID-5656130",
"CSAFPID-5656131",
"CSAFPID-5656132",
"CSAFPID-5656133",
"CSAFPID-5721197",
"CSAFPID-5772271",
"CSAFPID-5772272",
"CSAFPID-5840723",
"CSAFPID-5878928",
"CSAFPID-5878929"
]
},
"references": [
{
"category": "external",
"summary": "Source - nvd",
"url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-33683"
},
{
"category": "external",
"summary": "Source - cveprojectv5",
"url": "https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/33xxx/CVE-2026-33683.json"
},
{
"category": "external",
"summary": "Source - first",
"url": "https://api.first.org/data/v1/epss?limit=10000&offset=0"
},
{
"category": "external",
"summary": "Source - github",
"url": "https://api.github.com/advisories/GHSA-ghx5-7jjg-q2j7"
},
{
"category": "external",
"summary": "Source - osv",
"url": "https://www.googleapis.com/download/storage/v1/b/osv-vulnerabilities/o/Packagist%2FGHSA-ghx5-7jjg-q2j7.json?alt=media"
},
{
"category": "external",
"summary": "Reference - cveprojectv5; github; nvd; osv",
"url": "https://github.com/WWBN/AVideo/commit/7cfdc380dae1e56bbb5de581470d9e9957445df0"
},
{
"category": "external",
"summary": "Reference - cveprojectv5; github; nvd; osv",
"url": "https://github.com/WWBN/AVideo/security/advisories/GHSA-ghx5-7jjg-q2j7"
},
{
"category": "external",
"summary": "Reference - github; osv",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33683"
},
{
"category": "external",
"summary": "Reference - github",
"url": "https://github.com/advisories/GHSA-ghx5-7jjg-q2j7"
}
],
"scores": [
{
"cvss_v3": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N",
"baseScore": 5.4,
"baseSeverity": "MEDIUM"
},
"products": [
"CSAFPID-5656122",
"CSAFPID-5656123",
"CSAFPID-5656124",
"CSAFPID-5656125",
"CSAFPID-5656126",
"CSAFPID-5656127",
"CSAFPID-5656128",
"CSAFPID-5656129",
"CSAFPID-5656130",
"CSAFPID-5656131",
"CSAFPID-5656132",
"CSAFPID-5656133",
"CSAFPID-5721197",
"CSAFPID-5772271",
"CSAFPID-5772272",
"CSAFPID-5840723",
"CSAFPID-5878928",
"CSAFPID-5878929",
"CSAFPID-5893889"
]
}
],
"title": "CVE-2026-33683"
}
]
}