Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fa5c57ebbfd7242…

MALICIOUS

PDF

82.1 KB Created: 2021-09-15 16:47:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b809107caf1fe4b0a050a0e908c43f43 SHA-1: 3867b345df7d6d27168cbc83a001e7fc9881da7a SHA-256: 3fa5c57ebbfd7242fef505b7004241bf4b42b9bd6ea6c67f212a154406df7c6e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a link farm pointing to various PDF files hosted on potentially compromised or disposable domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a non-clustered link farm on disposable hosting, suggesting an attempt to distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://kisikana.hr/UserFiles/files/rokopozamizenefamof.pdf
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fa7e9ac60e---26555173508.pdf
    • https://www.comperat-89.fr/ckfinder/userfiles/files/pirupobef.pdf
    • http://nsdadventist.org/FCKData/file/tivupufumimikewonirubad.pdf
    • http://nadafashionbelt.com/Uploads/file/28237808043.pdf
    • http://cementfeet.com/userfiles/file/kurasosuz.pdf
    • http://rosritual.su/app/webroot/js/ckfinder/userfiles/files/moresuse.pdf
    • http://escritacontabilidade.net/fotos/news/file/73707323655.pdf
    • https://kimansion.com/uploads/file/tokibonawomuzivanav.pdf
    • https://toptenstudy.com/upload/files/BodyFile__612F57BFBFDD8.pdf
    • http://kochamsushi.pl/UserFiles/file/4986971024.pdf
    • https://kemxoi.vn/app/webroot/files/images/pages/files/9505111874.pdf
    • http://goldartline.ua/userfiles/file/suporivori.pdf
    • http://hftyby.com/upload_fck/file/2021-9-2/20210902120120587242.pdf
    • http://caogenzhiben.com/filespath/files/20210906074930.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/2gr1rr2rkq6l2jbmfibgmbrmct/43194479665.pdf
    • https://fereshtegan.net/basefile/fereshtegannet/files/mexojarotanu.pdf
    • https://olboihorgaszto.hu/editor_up2/70498080320.pdf
    • http://smartickgroup.com/userfiles/32291392867.pdf
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/16132daab821cc---lubiluzipapago.pdf
    • http://hylimusic.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/91879790861.pdf
    • https://foodphotoshop.com/userfiles/files/36577991504.pdf
    • http://smeeing.com/userfiles/files/98166743850.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=download+dumpster+mod+apk
    • 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_off0000db45.bin
46e2ab80aad20da8eccd21485a14a49783c83cee1c00847a1cb5893a0a7498c0
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB45 17884 bytes
font_01_sfnt_off000109ed.bin
747671fb8de82ec43ba5f2988bb8b5bc7e65a382db0aca38aa68eaae26a45b78
pdf-font-stream PDF embedded font (sfnt) at offset 0x109ED 10740 bytes
font_02_sfnt_off000122b6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x122B6 16792 bytes