Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a5abc9022f7a300…

MALICIOUS

PDF

75.4 KB Created: 2021-08-18 22:46:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ce65b1e032c60bca4ff93cd5eaed4a4a SHA-1: c8892ce64121b04ea0a66803bc86a5832dd4f4ab SHA-256: 4a5abc9022f7a30077ee8992ff4e354bbf2a554f3acb10bed4bce5b1825b380b
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to potentially compromised WordPress upload directories or disposable hosting. The document body was unreadable, but the presence of numerous external links suggests a phishing or SEO manipulation scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 http://jncs.kr/page_data/file/20210702075927.pdf In PDF document text
    • http://unicaconsultoriarh.com/images/files/tugukeromavevoxesotole.pdfIn PDF document text
    • http://liyangah.com/Upload/file/dogazuxoxodefakikugugavu.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c518a0eb469---10358039604.pdfIn PDF document text
    • http://steinemann-ag.ru/25264228221.pdfIn PDF document text
    • http://oaklandscreche.ie/userfiles/files/92620812858.pdfIn PDF document text
    • http://sushiosushi.com/uploads/files/duwebaxaweturitisizatok.pdfIn PDF document text
    • https://pass-eco-energies.com/ckfinder/userfiles/files/babolaxitexu.pdfIn PDF document text
    • http://sns.hu/_user/file/52917260072.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/8ir5b36jp0so517oe5r1ckbdh0/6558053180.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a0cf6163f2c---latuvupep.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/k7d2e450jbfiieutoihj7bb1f1/wupofim.pdfIn PDF document text
    • http://dirabrealtors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160738a68616c3---gobanugixenimisige.pdfIn PDF document text
    • http://spreewaldatelier.de/img/editor/file/nojeludigiri.pdfIn PDF document text
    • http://championshipsportsrings.com/clients/23492/File/9890061400.pdfIn PDF document text
    • https://big-affaires.com/img/pics/files/xukivujo.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608186f148997---viwetosajo.pdfIn PDF document text
    • https://ilcaminodaugo.it/file/10632817581.pdfIn PDF document text
    • http://xn----7sbakn3aoflleitf3m6a.xn--p1ai/userfiles/file/sadububavowebiposone.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/jn7s8nf3pn3th1bonhfma6lvap/femejivexozagedi.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/56fa955af294e01219495b69cee14cc1/basagosejogomamanurevapej.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/60qmp7403d9rn7toap6v9059c4/sasenadiperimiwowa.pdfIn PDF document text
    • http://cdseoulps.com/uploadfile/fckeditor/file/67651453835.pdfIn PDF document text
    • https://artenika.pl/fck/file/numuxaxozozodoruwubaniwe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=kambal+katinig+o+klaster+grade+2+halimbawaPDF 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_off0000c3f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3F8 16168 bytes
SHA-256: 35b801245e878a020d648c831a3adb1eade7e399a470214ffb1bc576c785c948
font_01_sfnt_off0000edaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDAF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000105c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105C6 11124 bytes
SHA-256: 6e0c832f9a5f14cda75dcc25e76c680069da220185698fa1ccc5af4ab126ed30