Vulnerability-Lookup

GHSA-WFQ5-QGQP-HVHV

Vulnerability from github – Published: 2026-03-17 20:05 – Updated: 2026-03-20 21:22

Summary

Unauthenticated Reflected XSS via innerHTML in AVideo

Details

Summary

AVideo contains a reflected XSS vulnerability that allows unauthenticated attackers to execute arbitrary JavaScript in a victim's browser. User input from a URL parameter flows through PHP's json_encode() into a JavaScript function that renders it via innerHTML, bypassing encoding and achieving full script execution.

Root Cause

The vulnerability is caused by two issues working together:

1. Source: Unescaped user input passed to JavaScript (videoNotFound.php)

File: view/videoNotFound.php line 49

if (!empty($_REQUEST['404ErrorMsg'])) {
    echo 'avideoAlertInfo(' . json_encode($_REQUEST['404ErrorMsg']) . ');';
}

PHP's json_encode() with default flags only escapes quotes (" → \") and backslashes. It does NOT escape HTML special characters (<, >, /). The resulting string contains raw HTML tags that are passed directly to JavaScript.

2. Sink: innerHTML renders HTML tags as executable DOM (script.js)

File: view/js/script.js

function avideoAlertInfo(msg) {            // line ~1891
    avideoAlert("", msg, 'info');           // calls ↓
}

function avideoAlert(title, msg, type) {   // line ~1270
    avideoAlertHTMLText(title, msg, type);  // calls ↓
}

function avideoAlertHTMLText(title, msg, type) {  // line ~1451
    var span = document.createElement("span");
    span.innerHTML = msg;                  // line 1464 — XSS SINK
    swal({ content: span });
}

innerHTML parses the string as HTML. Any <img>, <svg>, or other HTML tags with event handlers are instantiated as real DOM elements, triggering JavaScript execution.

Data Flow

URL parameter (?404ErrorMsg=PAYLOAD)
    → $_REQUEST['404ErrorMsg']
    → json_encode()          ← does NOT escape < > /
    → avideoAlertInfo()
    → avideoAlert()
    → avideoAlertHTMLText()
    → span.innerHTML = msg   ← renders HTML tags, executes JS

Proof of Concept

https://localhost/view/videoNotFound.php?404ErrorMsg=<img src=x onerror=alert(document.domain)>

The page renders:

avideoAlertInfo("<img src=x onerror=alert(document.domain)>");

Which flows to span.innerHTML = "<img src=x onerror=alert(document.domain)>". The browser creates an <img> element, src=x fails to load, onerror fires alert(document.domain).

Affected Code

File	Line	Issue
`view/videoNotFound.php`	49	`json_encode()` does not escape `<` `>` for HTML context
`view/js/script.js`	1464	`span.innerHTML = msg` renders user input as HTML
`view/js/script.js`	1282	`span.innerHTML = msg` in `avideoAlertWithCookie()`
`view/js/script.js`	1335	`span.innerHTML = __(msg,true)` in `avideoConfirm()`
`view/js/script.js`	1358	`span.innerHTML = msg` in `avideoAlertOnceForceConfirm()`

The innerHTML sink exists in 4 functions. Any future code that passes user input to avideoAlertInfo(), avideoAlertWarning(), avideoAlertDanger(), or avideoAlertSuccess() will create additional XSS vectors.

Remediation

Fix 1: Escape HTML in PHP (source fix)

// view/videoNotFound.php line 49
// BEFORE (vulnerable):
echo 'avideoAlertInfo(' . json_encode($_REQUEST['404ErrorMsg']) . ');';

// AFTER (fixed):
echo 'avideoAlertInfo(' . json_encode($_REQUEST['404ErrorMsg'], JSON_HEX_TAG | JSON_HEX_AMP) . ');';

JSON_HEX_TAG converts < → \u003C and > → \u003E, preventing HTML injection.

Fix 2: Use textContent instead of innerHTML (sink fix, recommended)

// view/js/script.js - all alert functions
// BEFORE (vulnerable):
span.innerHTML = msg;

// AFTER (fixed):
span.textContent = msg;

textContent treats the string as plain text — HTML tags are displayed literally, never parsed or executed.

Fix 3: Add Content-Security-Policy header (defense in depth)

Content-Security-Policy: default-src 'self'; script-src 'self'; style-src 'self' 'unsafe-inline'

Impact

Session hijacking — steal PHPSESSID cookie (not HttpOnly by default)
Account takeover — use stolen session to change password or email
Phishing — inject a realistic login form inside the SweetAlert modal
Worm propagation — inject self-spreading payloads via comments/messages
Admin compromise — send crafted link to admin, steal session, gain full control

Severity

5.3 (Medium)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "wwbn/avideo"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "25.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33035"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-17T20:05:23Z",
    "nvd_published_at": "2026-03-20T05:16:16Z",
    "severity": "MODERATE"
  },
  "details": "## Summary\n\nAVideo contains a reflected XSS vulnerability that allows unauthenticated attackers to execute arbitrary JavaScript in a victim\u0027s browser. User input from a URL parameter flows through PHP\u0027s `json_encode()` into a JavaScript function that renders it via `innerHTML`, bypassing encoding and achieving full script execution.\n\n\n## Root Cause\nThe vulnerability is caused by two issues working together:\n\n### 1. Source: Unescaped user input passed to JavaScript (videoNotFound.php)\n\n**File:** `view/videoNotFound.php` line 49\n\n```php\nif (!empty($_REQUEST[\u0027404ErrorMsg\u0027])) {\n    echo \u0027avideoAlertInfo(\u0027 . json_encode($_REQUEST[\u0027404ErrorMsg\u0027]) . \u0027);\u0027;\n}\n```\n\nPHP\u0027s `json_encode()` with default flags only escapes quotes (`\"` \u2192 `\\\"`) and backslashes. It does **NOT** escape HTML special characters (`\u003c`, `\u003e`, `/`). The resulting string contains raw HTML tags that are passed directly to JavaScript.\n\n### 2. Sink: innerHTML renders HTML tags as executable DOM (script.js)\n\n**File:** `view/js/script.js`\n\n```javascript\nfunction avideoAlertInfo(msg) {            // line ~1891\n    avideoAlert(\"\", msg, \u0027info\u0027);           // calls \u2193\n}\n\nfunction avideoAlert(title, msg, type) {   // line ~1270\n    avideoAlertHTMLText(title, msg, type);  // calls \u2193\n}\n\nfunction avideoAlertHTMLText(title, msg, type) {  // line ~1451\n    var span = document.createElement(\"span\");\n    span.innerHTML = msg;                  // line 1464 \u2014 XSS SINK\n    swal({ content: span });\n}\n```\n\n`innerHTML` parses the string as HTML. Any `\u003cimg\u003e`, `\u003csvg\u003e`, or other HTML tags with event handlers are instantiated as real DOM elements, triggering JavaScript execution.\n\n### Data Flow\n\n```\nURL parameter (?404ErrorMsg=PAYLOAD)\n    \u2192 $_REQUEST[\u0027404ErrorMsg\u0027]\n    \u2192 json_encode()          \u2190 does NOT escape \u003c \u003e /\n    \u2192 avideoAlertInfo()\n    \u2192 avideoAlert()\n    \u2192 avideoAlertHTMLText()\n    \u2192 span.innerHTML = msg   \u2190 renders HTML tags, executes JS\n```\n\n---\n\n## Proof of Concept\n```\nhttps://localhost/view/videoNotFound.php?404ErrorMsg=\u003cimg src=x onerror=alert(document.domain)\u003e\n```\n\u003cimg width=\"1918\" height=\"1035\" alt=\"image\" src=\"https://github.com/user-attachments/assets/20077ce2-5b49-4bd3-a7df-ab48be786cc1\" /\u003e\n\nThe page renders:\n```javascript\navideoAlertInfo(\"\u003cimg src=x onerror=alert(document.domain)\u003e\");\n```\n\nWhich flows to `span.innerHTML = \"\u003cimg src=x onerror=alert(document.domain)\u003e\"`. The browser creates an `\u003cimg\u003e` element, `src=x` fails to load, `onerror` fires `alert(document.domain)`.\n\n## Affected Code\n\n| File | Line | Issue |\n|------|------|-------|\n| `view/videoNotFound.php` | 49 | `json_encode()` does not escape `\u003c` `\u003e` for HTML context |\n| `view/js/script.js` | 1464 | `span.innerHTML = msg` renders user input as HTML |\n| `view/js/script.js` | 1282 | `span.innerHTML = msg` in `avideoAlertWithCookie()` |\n| `view/js/script.js` | 1335 | `span.innerHTML = __(msg,true)` in `avideoConfirm()` |\n| `view/js/script.js` | 1358 | `span.innerHTML = msg` in `avideoAlertOnceForceConfirm()` |\n\nThe `innerHTML` sink exists in 4 functions. Any future code that passes user input to `avideoAlertInfo()`, `avideoAlertWarning()`, `avideoAlertDanger()`, or `avideoAlertSuccess()` will create additional XSS vectors.\n\n\n## Remediation\n\n### Fix 1: Escape HTML in PHP (source fix)\n\n```php\n// view/videoNotFound.php line 49\n// BEFORE (vulnerable):\necho \u0027avideoAlertInfo(\u0027 . json_encode($_REQUEST[\u0027404ErrorMsg\u0027]) . \u0027);\u0027;\n\n// AFTER (fixed):\necho \u0027avideoAlertInfo(\u0027 . json_encode($_REQUEST[\u0027404ErrorMsg\u0027], JSON_HEX_TAG | JSON_HEX_AMP) . \u0027);\u0027;\n```\n\n`JSON_HEX_TAG` converts `\u003c` \u2192 `\\u003C` and `\u003e` \u2192 `\\u003E`, preventing HTML injection.\n\n### Fix 2: Use textContent instead of innerHTML (sink fix, recommended)\n\n```javascript\n// view/js/script.js - all alert functions\n// BEFORE (vulnerable):\nspan.innerHTML = msg;\n\n// AFTER (fixed):\nspan.textContent = msg;\n```\n\n`textContent` treats the string as plain text \u2014 HTML tags are displayed literally, never parsed or executed.\n\n### Fix 3: Add Content-Security-Policy header (defense in depth)\n\n```\nContent-Security-Policy: default-src \u0027self\u0027; script-src \u0027self\u0027; style-src \u0027self\u0027 \u0027unsafe-inline\u0027\n```\n\n## Impact\n\n- **Session hijacking** \u2014 steal `PHPSESSID` cookie (not HttpOnly by default)\n- **Account takeover** \u2014 use stolen session to change password or email\n- **Phishing** \u2014 inject a realistic login form inside the SweetAlert modal\n- **Worm propagation** \u2014 inject self-spreading payloads via comments/messages\n- **Admin compromise** \u2014 send crafted link to admin, steal session, gain full control",
  "id": "GHSA-wfq5-qgqp-hvhv",
  "modified": "2026-03-20T21:22:24Z",
  "published": "2026-03-17T20:05:23Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/WWBN/AVideo/security/advisories/GHSA-wfq5-qgqp-hvhv"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33035"
    },
    {
      "type": "WEB",
      "url": "https://github.com/WWBN/AVideo/commit/cca6196f4072cb9acc39b1030fb8fb1702b4f69b"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/WWBN/AVideo"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Unauthenticated Reflected XSS via innerHTML in AVideo"
}

CVE-2026-33035 (GCVE-0-2026-33035)

Vulnerability from cvelistv5 – Published: 2026-03-20 05:08 – Updated: 2026-03-20 15:40

Title

Unauthenticated Reflected XSS via innerHTML in AVideo

Summary

WWBN AVideo is an open source video platform. In versions 25.0 and below, there is a reflected XSS vulnerability that allows unauthenticated attackers to execute arbitrary JavaScript in a victim's browser. User input from a URL parameter flows through PHP's json_encode() into a JavaScript function that renders it via innerHTML, bypassing encoding and achieving full script execution. The vulnerability is caused by two issues working together: unescaped user input passed to JavaScript (videoNotFound.php), and innerHTML rendering HTML tags as executable DOM (script.js). The attack can be escalated to steal session cookies, take over accounts, phish credentials via injected login forms, spread self-propagating payloads, and compromise admin accounts — all by exploiting the lack of proper input sanitization and cookie security (e.g., missing HttpOnly flag on PHPSESSID). The issue has been fixed in version 26.0.

Severity

5.3 (Medium)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-03-20 15:39 UTC

CWE

CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Assigner

GitHub_M mitre root

References

2 references

URL	Tags
https://github.com/WWBN/AVideo/security/advisorie…	x_refsource_CONFIRM
https://github.com/WWBN/AVideo/commit/cca6196f407…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
WWBN	AVideo	Affected: < 26.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-33035",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-20T15:39:55.846227Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-03-20T15:40:13.134Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "AVideo",
          "vendor": "WWBN",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 26.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "WWBN AVideo is an open source video platform. In versions 25.0 and below, there is a reflected XSS vulnerability that allows unauthenticated attackers to execute arbitrary JavaScript in a victim\u0027s browser. User input from a URL parameter flows through PHP\u0027s json_encode() into a JavaScript function that renders it via innerHTML, bypassing encoding and achieving full script execution. The vulnerability is caused by two issues working together: unescaped user input passed to JavaScript (videoNotFound.php), and innerHTML rendering HTML tags as executable DOM (script.js).  The attack can be escalated to steal session cookies, take over accounts, phish credentials via injected login forms, spread self-propagating payloads, and compromise admin accounts \u2014 all by exploiting the lack of proper input sanitization and cookie security (e.g., missing HttpOnly flag on PHPSESSID). The issue has been fixed in version 26.0."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "LOW",
            "subIntegrityImpact": "LOW",
            "userInteraction": "PASSIVE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-79",
              "description": "CWE-79: Improper Neutralization of Input During Web Page Generation (\u0027Cross-site Scripting\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-03-20T05:09:03.649Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/WWBN/AVideo/security/advisories/GHSA-wfq5-qgqp-hvhv",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/WWBN/AVideo/security/advisories/GHSA-wfq5-qgqp-hvhv"
        },
        {
          "name": "https://github.com/WWBN/AVideo/commit/cca6196f4072cb9acc39b1030fb8fb1702b4f69b",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/WWBN/AVideo/commit/cca6196f4072cb9acc39b1030fb8fb1702b4f69b"
        }
      ],
      "source": {
        "advisory": "GHSA-wfq5-qgqp-hvhv",
        "discovery": "UNKNOWN"
      },
      "title": "Unauthenticated Reflected XSS via innerHTML in AVideo"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-33035",
    "datePublished": "2026-03-20T05:08:31.540Z",
    "dateReserved": "2026-03-17T18:10:50.209Z",
    "dateUpdated": "2026-03-20T15:40:13.134Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

GHSA-WFQ5-QGQP-HVHV

Summary

Root Cause

1. Source: Unescaped user input passed to JavaScript (videoNotFound.php)

2. Sink: innerHTML renders HTML tags as executable DOM (script.js)

Data Flow

Proof of Concept

Affected Code

Remediation

Fix 1: Escape HTML in PHP (source fix)

Fix 2: Use textContent instead of innerHTML (sink fix, recommended)

Fix 3: Add Content-Security-Policy header (defense in depth)

Impact

CVE-2026-33035 (GCVE-0-2026-33035)

Tags

Sightings

Nomenclature

Related by attack behaviour