Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b00a028a956d670…

MALICIOUS

PDF

74.4 KB Created: 2021-09-02 12:11:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: fa53556dd0c0469c2cc811d02efc4223 SHA-1: 083e98399a43ce5262c53c8de3fcca4f53c0c8e5 SHA-256: 1b00a028a956d6706f219a10fffe7abbf3f7ccf5b620fefe86fb6853dbc13d6d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with numerous links pointing to potentially compromised or disposable hosting sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather to facilitate the link farm functionality.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://emannsltd.com/userfiles/8586166102.pdf In PDF document text
    • http://modnyi-buket.ru/uploads/files/77301156499.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a5f2aa27706---magupefikedarugodub.pdfIn PDF document text
    • http://icsbc.ru/fuploader//file/xarolinemorawi.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160afdb52bfee3---limukexizavixiseladoras.pdfIn PDF document text
    • http://bizbecho.com/pa/trainstation/uploads/image/file/rubatarugavodixoxaz.pdfIn PDF document text
    • http://consade.com/userfiles/file/90924775933.pdfIn PDF document text
    • http://bigyikesmedia.com/home/xtremweb/public_html/consultinstitute/web/upload/files/37216977191.pdfIn PDF document text
    • http://argyler.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073b3ebaf133---silowiturakapidorul.pdfIn PDF document text
    • https://mebelihome.ru/upload_picture/17898212690.pdfIn PDF document text
    • https://aristi-trap.com/upload/users/files/butinobowoxaveretupedisa.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16119ff913ca98---83396963625.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///litadomarisuritalezoma.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/16093aa6aa140e---74021980853.pdfIn PDF document text
    • http://mfo-fond.ru/ckeditor/ckfinder/userfiles/Images/files/rugilipufisagipetetawu.pdfIn PDF document text
    • https://webmenuplus.com/images/file/puwedokafapawodi.pdfIn PDF document text
    • http://geologicatoscana.eu/userfiles/files/50968499903.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16125046ce3cf6---lazibabugiwanidip.pdfIn PDF document text
    • https://tch.lu/files/files/90853566875.pdfIn PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/lgf7ajhldv3bt2pen2a4bl5gn2/29844304265.pdfIn PDF document text
    • https://prcomponents.com/ckfinder/userfiles/files/kokebalavixobugopudot.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/bc9utp72nhvs2bob10fl84j74l/nidefurofovoviregetila.pdfIn PDF document text
    • http://mispuntossaga.com/campannas/file/49408072622.pdfIn PDF document text
    • http://resortvillairene.it/userfiles/files/sivowezurixixalejuwiruzu.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/9d75988a573fb5eb81fa4dc8fdbf8e82/baxibazuwiveve.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=electric+circuit+components+worksheetPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c22b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC22B 16008 bytes
SHA-256: 609426c08cf822ceaab069932260125fc6bae7dedb2d430106900d963dee887b
font_01_sfnt_off0000eb73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB73 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001038a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1038A 10740 bytes
SHA-256: 016f57b77a642fd47560783d9a8d7536c878dcb7d593fee3524fa53408ec25a3