Malicious PDF — malware analysis report

Static analysis result for SHA-256 8085786d3ca8ce00…

MALICIOUS

PDF

69.6 KB Created: 2021-09-29 03:25:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 5283206905289d170b6e01aab99d4dc4 SHA-1: 12ab4a3e615f826cfe3860805685a99e5d93ad39 SHA-256: 8085786d3ca8ce00c06ac0589a5b396c84084069d68a3bbf63bd3555d221711f
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and ML classifiers indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised WordPress uploads and disposable hosting, with external URIs like https://crysiq.ru/uplcv?utm_term=bobby+hd+apk. The document body is heavily obfuscated and unreadable, suggesting it's designed to hide its malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • 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://crysiq.ru/uplcv?utm_term=bobby+hd+apk PDF link annotation
    • http://lblussana.it/images/file/duwetugodoke.pdfIn PDF document text
    • http://uekekb.ru/!upload/files/90436487962.pdfIn PDF document text
    • https://bushregenerators.biz/userfiles/files/10937642550.pdfIn PDF document text
    • http://mayingiabao.com/upload/files/22262362791.pdfIn PDF document text
    • https://demoepaper.104portal.com/upload/serback/files/20210925074812.pdfIn PDF document text
    • https://kvzriu.org/images/file/5276864929.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/16139f4dbbedab---5007399598.pdfIn PDF document text
    • http://dnt-mayak.ru/content/File/sixepubekadusaj.pdfIn PDF document text
    • http://www.darvidproperty.com/news/file/wamulawomuzoluwima.pdfIn PDF document text
    • https://aljazeerahpetroleum.ae/userfiles/files/donozudinegit.pdfIn PDF document text
    • http://fazendasaojudastadeu.net/fotosempresa/files/megirinero.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161400794b47c4---41143561444.pdfIn PDF document text
    • http://ccadl.com/files/20210912171934.pdfIn PDF document text
    • http://thunderstar.cn/userfiles/file/20210906124835622991283.pdfIn PDF document text
    • http://vladekoservis.ru/files/74714324514.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1614fb24e69229---zenipojaviwelide.pdfIn PDF document text
    • https://surupaceanu.ro/ckfinder/userfiles/files/48532134238.pdfIn PDF document text
    • http://sladkiy-ostrov.ru/userfiles/files/25940360468.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/2998adbfe82816140ca7319c5880176b/xebigubogejivubetoxi.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/80b5vhp6ludvc99pbnpurk8gq7/viroju.pdfIn PDF document text
    • http://www.fdconsult.qa/public/uploads/cms_files/vadoriduvek.pdfIn PDF document text
    • http://gamax-moto.cz/data/dokumenty/kugodutisirojakajotolusa.pdfIn PDF document text
    • https://coffeetuanvang.com/Images_upload/files/zuwuvaki.pdfIn PDF document text
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/losejufebaribidog.pdfIn PDF document text
    • http://vit-physio.de/file/51608831376.pdfIn 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://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_off0000b341.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB341 10148 bytes
SHA-256: 0ca3e43f4fb007570c7baead5c222317012acfa7f24197ab27cfed2044ce59f2
font_01_sfnt_off0000c9d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e1e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1E8 15392 bytes
SHA-256: 0e8640fbf38e94cb50f7e431e2b4ab39327dc1d0832a244da98090c984e00192