Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4135809219ad477…

MALICIOUS

PDF

74.3 KB Created: 2021-06-07 12:07:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 5e61ec13a0ecb72cfad75991ac25cdb2 SHA-1: 91ea2601001ca31b3815b196bc7b9b4ef54dfa42 SHA-256: b4135809219ad477db3db7e84bc70a31acee7040002b8b363baff00a011b9080
164 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://cructi.ru/uplcv?utm_term=aashto+bridge+design+manual PDF link annotation
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d50ee93ae4---99484942185.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16093c6cbc2047---22121878561.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/jdbc4c37mgd7lpdsnsr7ebldf1/35046534436.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160a6aef090775---nisoremafigapugowizokupo.pdfIn PDF document text
    • https://led7.ru/file/mumun.pdfIn PDF document text
    • http://cbgnfinance.com/userfiles/file/tivopepimikitutizusexalup.pdfIn PDF document text
    • http://staractivecollection.com/resimler/site/files/bafosoris.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c7609a4fe1---desojike.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/49ae9afa16a65c84a360a43f936aeffa/30068641802.pdfIn PDF document text
    • https://superpart.com/files/59665502682.pdfIn PDF document text
    • http://docando.es/js/ckfinder/userfiles/files/78135650800.pdfIn PDF document text
    • https://emauto.lv/index/images/up/file/pakepamagaru.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608885d44c5e0---74703808848.pdfIn PDF document text
    • http://koryosushi.com/uploads/files/50485842807.pdfIn PDF document text
    • https://www.alarisusallc.com/wp-content/plugins/super-forms/uploads/php/files/777511bd2fb1642edfd09f4341c0e6a6/21060008618.pdfIn PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a13e35cc5c---22466693710.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609063a62e2ae---96196528566.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d99b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD99B 5252 bytes
SHA-256: 4c1ca036a3d0abce605190280a1cc941a99acf7aa533be07aab1ff3c28b2d265
font_01_sfnt_off0000eb41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB41 10332 bytes
SHA-256: 182a489744aafacdc9f9001f6ca613c34b77430a2b790bb368b5c8db803cb8aa
font_02_sfnt_off00010e63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E63 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2