Malicious PDF — malware analysis report

Static analysis result for SHA-256 b50ee2fcb297f76b…

MALICIOUS

PDF

84.4 KB Created: 2021-07-20 17:56:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: aa8df7a9f100547bf9137b06926096e8 SHA-1: 55a51d02ba96242bc61626fadd6473e0be62cc61 SHA-256: b50ee2fcb297f76b0096f227f9ccd3e09081bb70fb6b030a71e804630e436ae7
204 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and a link farm pointing to multiple PDF files hosted on various domains, some of which appear to be compromised WordPress sites. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' indicates the document likely instructs the user to open a password-protected archive, a common tactic to bypass gateway scanning. The ML classifier and ClamAV detection strongly suggest malicious intent, likely a phishing or trojan delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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 http://skiflogistics.ru/userfiles/file/vetepa.pdf
    • http://www.irrv.org/uploads/files/27801098395.pdf
    • http://sinproval.it/userfiles/files/namadijasisufoleziteli.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c63fd3c2254---ladifabutewojizajajopape.pdf
    • https://airshow-bg.com/file/fizezebujidumekep.pdf
    • http://www.enjoyvaltellina.it/admin/ckfinder/userfiles/files/xugafutunusa.pdf
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097b8b6cf429---21372166423.pdf
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160be33a34452c---37379503539.pdf
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/d3024a0207f8e86f0e33dad57ae83ee4/51694026905.pdf
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/160abd7e800438---81711019411.pdf
    • http://ivepe-elearning.gr/assets/UserFiles/mainHome/file/zajanis.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/160a0b43355992---52555687378.pdf
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608ac080598b4---84354726603.pdf
    • http://shipagents.nl/uploadfiles/file/11735877839.pdf
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/160afd4ebe7240---fulewadobadoxitozuma.pdf
    • http://inbjnews.com/data/cheditor/0603/files/17041657406.pdf
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f02d0936b7---41991481539.pdf
    • http://fixmyhelicopter.com/project-new/christianbook/upload_images/file/nowitapazabixoku.pdf
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160861febb470e---luvagikubibo.pdf
    • https://digireg.gr/upload/susabopi.pdf
    • http://graphicyazd.com/ckfinder/userfiles/files/nifujodadoxoxugur.pdf
    • http://kingsauto-bar.com/js/upload/files/80878768984.pdf
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16087706b63ebf---60645895724.pdf
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/64bc6109a3ee11d8d2dee2b182a9678c/97393341314.pdf
    • http://fixafilm.se/userfiles/file/vuxake.pdf
    • http://www.allatpatikapecs.hu/images/file/mowubamudopixarabagotoni.pdf
    • https://binarbaidequipment.com/public_html/userfiles/file/94713413008.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=how+to+combine+multiple+files+into+one+file
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e4ea.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE4EA 16792 bytes
font_01_sfnt_off0000fcfc.bin
92d7786f6c5185ed38437ef738c3074a513bccdae5b4acc943feec303d35b60f
pdf-font-stream PDF embedded font (sfnt) at offset 0xFCFC 17660 bytes
font_02_sfnt_off00012b62.bin
00a6ee3a7d7514d82ff8c178de9a22749ca5a95348bd124dfd32cfc02a967bf4
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B62 10696 bytes