Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b66fce11cc364ea…

MALICIOUS

PDF

95.1 KB Created: 2021-06-26 04:24:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 702f0d6c5eb5ee65f1f7e413b84681f1 SHA-1: 64171f24c4ea2156a81a0e54188710e422caca54 SHA-256: 6b66fce11cc364eaae76c7d161943906c5377197a1135bc8de68cff28553acf8
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many hosted on compromised CMS platforms, indicating a link farm designed to lead users to malicious sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://nomylo.ru/uplcv?utm_term=what+is+higher+ed PDF link annotation
    • https://supermagnum-bg.com/ckfinder/userfiles/files/75812954515.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/u2t3d2n7ank0j2gvhb3lisjnl1/56557990738.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/88e619eb1600993cf8d8e39088109c29/58089327768.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a06de34694a---6442929066.pdfIn PDF document text
    • http://cc-loges.com/uploads/file/woxakilepezodijem.pdfIn PDF document text
    • https://akamercedes.com/images/uploads/files/84720647539.pdfIn PDF document text
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/1a1c246929eaf4deae4123d087b73444/16765834414.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b661b50d047---diwufadaza.pdfIn PDF document text
    • http://manpukuorder.com/uploads/files/27825745059.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/5d599abd78ddd561d59efd87ce1719d9/zasegeve.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/517fd0d2a18b945d73c0775dc738f69e/86731883030.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160730f0330818---mavud.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/73c47a66baaefac46f585b06026f9c39/52809948243.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bc86f85dce---14362904289.pdfIn PDF document text
    • http://www.everhouse.lt/wp-content/plugins/formcraft/file-upload/server/content/files/160993f06a8927---vunesesesu.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/160a41385bb9e8---gelepafibevovowufofirive.pdfIn PDF document text
    • https://littlelightnepal.org/userfiles/file/54495224141.pdfIn PDF document text
    • http://krevue.cz/UserFiles/File/43999970579.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a89a7b942ab---23799605512.pdfIn PDF document text
    • http://auchli-appenzeller.ch/userfiles/files/3134798361.pdfIn PDF document text
    • http://bouncebodysupplements.com/newerac2c/userfiles/file/pupabo.pdfIn PDF document text
    • http://purpledoorchurch.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b7b3a8637c---sasaguwebibizolo.pdfIn PDF document text
    • https://laser123.com/geektic/files/9958501133.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_off00010d6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D6E 19284 bytes
SHA-256: f67dd594df43a9ac67ded8fdea7a43d9dc9c2846ea2c03ae73dba6a591ab84aa
font_01_sfnt_off00013ee2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EE2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000156f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156F9 10252 bytes
SHA-256: 131727edbc1b41dce63d83447b5e51354542c81057bc4001c3e7614c2f045574