Add Socket patch for CVE-2026-25896 in pkg:npm/fast-xml-parser@4.2.5

.socket/blob/9ef2c515611c8a1f613c683b3f52893f98ce502572a14302e3a9ad048e98e991

@@ -0,0 +1,171 @@
+// Socket Community Patch: https://socket.dev
+// Date: Mon, 16 Mar 2026 22:26:53 GMT
+// For more information see https://socket.dev/patch/36d88172-e418-4019-ae59-88a7fdf6a1a6
+// This file includes modifications made by Socket, Inc. on Mon, 16 Mar 2026; these modifications are called the "Patch". In some cases, Socket may be required to make the Patch available to you under specific terms, or may be prohibited from restricting certain rights you may have. For example, the terms of another applicable license may require Socket to make the Patch available under specific terms. In those cases, the Patch is made available to you under the required terms, and Socket does not seek to restrict your rights relative to the Patch where prohibited. In all other cases, the Patch is available to you exclusively under the PolyForm Shield License 1.0.0 (https://polyformproject.org/licenses/shield/1.0.0/). The Patch was distributed by Socket with additional information concerning licensing, attribution, and limitation of liability which may be relevant to you and your use of the Patch. As far as the law allows, the Patch and the software including the patch come as is, without any warranty or condition, and Socket will not be liable to you for any damages arising out of the applicable license terms or the use or nature of the Patch or the software including the patch, under any kind of legal claim.
+// Original License: MIT
+
+const util = require('../util');
+
+//TODO: handle comments
+function readDocType(xmlData, i){
+
+    const entities = {};
+    if( xmlData[i + 3] === 'O' &&
+         xmlData[i + 4] === 'C' &&
+         xmlData[i + 5] === 'T' &&
+         xmlData[i + 6] === 'Y' &&
+         xmlData[i + 7] === 'P' &&
+         xmlData[i + 8] === 'E')
+    {    
+        i = i+9;
+        let angleBracketsCount = 1;
+        let hasBody = false, comment = false;
+        let exp = "";
+        for(;i<xmlData.length;i++){
+            if (xmlData[i] === '<' && !comment) { //Determine the tag type
+                if( hasBody && isEntity(xmlData, i)){
+                    i += 7; 
+                    [entityName, val,i] = readEntityExp(xmlData,i+1);
+                    if(val.indexOf("&") === -1) { //Parameter entities are not supported
+                        const escaped = entityName.replace(/[.\-+*:]/g, '\\.');
+                        entities[ validateEntityName(entityName) ] = {
+                            regx : RegExp( `&${escaped};`,"g"),
+                            val: val
+                        };
+                    }
+                }
+                else if( hasBody && isElement(xmlData, i))  i += 8;//Not supported
+                else if( hasBody && isAttlist(xmlData, i))  i += 8;//Not supported
+                else if( hasBody && isNotation(xmlData, i)) i += 9;//Not supported
+                else if( isComment)                         comment = true;
+                else                                        throw new Error("Invalid DOCTYPE");
+
+                angleBracketsCount++;
+                exp = "";
+            } else if (xmlData[i] === '>') { //Read tag content
+                if(comment){
+                    if( xmlData[i - 1] === "-" && xmlData[i - 2] === "-"){
+                        comment = false;
+                        angleBracketsCount--;
+                    }
+                }else{
+                    angleBracketsCount--;
+                }
+                if (angleBracketsCount === 0) {
+                  break;
+                }
+            }else if( xmlData[i] === '['){
+                hasBody = true;
+            }else{
+                exp += xmlData[i];
+            }
+        }
+        if(angleBracketsCount !== 0){
+            throw new Error(`Unclosed DOCTYPE`);
+        }
+    }else{
+        throw new Error(`Invalid Tag instead of DOCTYPE`);
+    }
+    return {entities, i};
+}
+
+function readEntityExp(xmlData,i){
+    //External entities are not supported
+    //    <!ENTITY ext SYSTEM "http://normal-website.com" >
+
+    //Parameter entities are not supported
+    //    <!ENTITY entityname "&anotherElement;">
+
+    //Internal entities are supported
+    //    <!ENTITY entityname "replacement text">
+
+    // Skip leading whitespace
+    while (i < xmlData.length && /\s/.test(xmlData[i])) i++;
+
+    //read EntityName - stop at whitespace or quote
+    let entityName = "";
+    while (i < xmlData.length && !/\s/.test(xmlData[i]) && xmlData[i] !== "'" && xmlData[i] !== '"') {
+        entityName += xmlData[i];
+        i++;
+    }
+    validateEntityName(entityName);
+
+    // Skip whitespace between name and value
+    while (i < xmlData.length && /\s/.test(xmlData[i])) i++;
+
+    // Check for unsupported constructs
+    if (xmlData.substring(i, i + 6).toUpperCase() === "SYSTEM") {
+        throw new Error("External entities are not supported");
+    } else if (xmlData[i] === "%") {
+        throw new Error("Parameter entities are not supported");
+    }
+
+    //read Entity Value
+    const startChar = xmlData[i++];
+    let val = ""
+    for (; i < xmlData.length && xmlData[i] !== startChar ; i++) {
+        val += xmlData[i];
+    }
+    return [entityName, val, i];
+}
+
+function isComment(xmlData, i){
+    if(xmlData[i+1] === '!' &&
+    xmlData[i+2] === '-' &&
+    xmlData[i+3] === '-') return true
+    return false
+}
+function isEntity(xmlData, i){
+    if(xmlData[i+1] === '!' &&
+    xmlData[i+2] === 'E' &&
+    xmlData[i+3] === 'N' &&
+    xmlData[i+4] === 'T' &&
+    xmlData[i+5] === 'I' &&
+    xmlData[i+6] === 'T' &&
+    xmlData[i+7] === 'Y') return true
+    return false
+}
+function isElement(xmlData, i){
+    if(xmlData[i+1] === '!' &&
+    xmlData[i+2] === 'E' &&
+    xmlData[i+3] === 'L' &&
+    xmlData[i+4] === 'E' &&
+    xmlData[i+5] === 'M' &&
+    xmlData[i+6] === 'E' &&
+    xmlData[i+7] === 'N' &&
+    xmlData[i+8] === 'T') return true
+    return false
+}
+
+function isAttlist(xmlData, i){
+    if(xmlData[i+1] === '!' &&
+    xmlData[i+2] === 'A' &&
+    xmlData[i+3] === 'T' &&
+    xmlData[i+4] === 'T' &&
+    xmlData[i+5] === 'L' &&
+    xmlData[i+6] === 'I' &&
+    xmlData[i+7] === 'S' &&
+    xmlData[i+8] === 'T') return true
+    return false
+}
+function isNotation(xmlData, i){
+    if(xmlData[i+1] === '!' &&
+    xmlData[i+2] === 'N' &&
+    xmlData[i+3] === 'O' &&
+    xmlData[i+4] === 'T' &&
+    xmlData[i+5] === 'A' &&
+    xmlData[i+6] === 'T' &&
+    xmlData[i+7] === 'I' &&
+    xmlData[i+8] === 'O' &&
+    xmlData[i+9] === 'N') return true
+    return false
+}
+
+function validateEntityName(name){
+    if (util.isName(name))
+	return name;
+    else
+        throw new Error(`Invalid entity name ${name}`);
+}
+
+module.exports = readDocType;