Malicious PDF — malware analysis report

Static analysis result for SHA-256 900686afc81bc82f…

MALICIOUS

PDF

74.9 KB Created: 2021-09-18 15:54:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: af3a20ae55a9d93c77c9a747ec338915 SHA-1: a4c1f0be79f2514440be36d20cd667d82f28e180 SHA-256: 900686afc81bc82f04192e71e7010f5186d85e1c43743274941a1130ce9724bc
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It functions as a link farm, containing numerous embedded URLs that point to various websites. Several of these URLs lead to compromised WordPress installations, suggesting an attempt to leverage these sites for phishing or to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://queure.ru/uplcv?utm_term=avatar+2009+full+movie+free+download PDF link annotation
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16133cdaaf2d2b---17631024718.pdfIn PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/dv7lq92lbqcojnl4robi8jjp32/92892576592.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e001879729---luwuxije.pdfIn PDF document text
    • http://radtel-sport.pl/userfiles/file/nonusomewijizej.pdfIn PDF document text
    • http://topspeed4wd.com/ckfinder/userfiles/files/tapalujiwenudogupokevip.pdfIn PDF document text
    • https://idroilektriki.gr/files/file/pimatanez.pdfIn PDF document text
    • https://landtop.com/filespath/files/20210902200109.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1614127a9b7d6d---kadekisesidedu.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1614529860292c---matamaxakolepupam.pdfIn PDF document text
    • http://familiegravesen.dk/ckfinder/userfiles/files/jepafefitugasose.pdfIn PDF document text
    • http://abwcoliseum.com/uploads/files/sosil.pdfIn PDF document text
    • https://coffotea.com/uploads/files/202109010544587866.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-9-8/20210908150750363329.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613407b598bbc---72677366411.pdfIn PDF document text
    • http://twtipa.com/upfile/files/2021/09/08/30568555848.pdfIn PDF document text
    • http://lakshimi-kaatsu.com/user_data/packages/default/imgfiles/vopipuvetakifubavi.pdfIn PDF document text
    • http://hotelrealerimini.it/userfiles/files/muzelufetojejus.pdfIn PDF document text
    • http://doradcyprawni.com/images/pliki/kusevafiselikuzopavanur.pdfIn PDF document text
    • http://alnoorcity.com/userfiles/file/82799920083.pdfIn PDF document text
    • http://altinay-law.com/images/file/26249880109.pdfIn PDF document text
    • http://britishcytology.org.uk/ckfinder/userfiles/files/pitagetirakoved.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613b707be4291---jisopimipunitisogaxa.pdfIn PDF document text
    • http://wwpokebar.com/uploads/files/jiwugaganu.pdfIn PDF document text
    • http://chiangmai-esc.net/user_img/files/dumugaligod.pdfIn PDF document text
    • http://xn--franzsischebulldoggen-lec.eu/userfiles/file/48785769385.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_off0000bef5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBEF5 10992 bytes
SHA-256: 490fa2755ffd0fa1aea8a1a93d0479503a1215db87dfbbd792d75fce7c2f4074
font_01_sfnt_off0000d899.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD899 17516 bytes
SHA-256: 313e0c8dae1664b1da5562803961bc3b4318c20bd1f7809799e0a6d7c732e994
font_02_sfnt_off000105f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1