Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a7dcaa381fcbe12…

MALICIOUS

PDF

86.4 KB Created: 2021-07-13 16:43:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: d16bb39f1c49b76fd17933f9ca42ee42 SHA-1: 02672c2819f2a4e2fb639a46baa3d99171107dd8 SHA-256: 8a7dcaa381fcbe1272b1fd17c493c3ff9e398bb0185340d6efb201116293d7ab
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. It contains numerous links pointing to compromised CMS uploads and disposable hosting, indicating a link farm designed to redirect users to malicious sites. The presence of multiple compromised upload URLs suggests an attempt to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.aserspa.net/wp-content/plugins/super-forms/uploads/php/files/cema73mgi768srmeim1e1e6oc1/62989410838.pdf In PDF document text
    • http://daydreamspin.com/userfiles/file/16748615909.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160bfb48c07db8---werupuk.pdfIn PDF document text
    • http://enjoybowlramenandpoke.com/uploads/files/nikugezumorut.pdfIn PDF document text
    • https://petrovsky14.ru/docs/files/86967015335.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d23ece22604---gaxoropusotolokalewovew.pdfIn PDF document text
    • http://almar-bus.pl/userfiles/file/pojafuvulegemowu.pdfIn PDF document text
    • http://brilliantsolarpaneling.com/userfiles/file/detinemamexusezumisujes.pdfIn PDF document text
    • http://cariboohose.com/userfiles/file/54739521963.pdfIn PDF document text
    • http://clinicaveterinariabilancino.it/userfiles/files/nujor.pdfIn PDF document text
    • http://www.mezmat.ru/ckfinder/userfiles/files/49445463345.pdfIn PDF document text
    • https://fonixkoncert.hu/upload/file/78754921378.pdfIn PDF document text
    • http://marinapogon.pl/upload/file/kokikejepewuwagalamegug.pdfIn PDF document text
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/acfqgh4ldfml71jvjpbkcnksp2/77548481646.pdfIn PDF document text
    • https://aspaeng.com/files/image/files/68853977277.pdfIn PDF document text
    • http://aqbnb.com/uploadfile/file/wetej.pdfIn PDF document text
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/dqt3aga1hl8gvoa82enb9b1cc0/gevukixunotafivuvelat.pdfIn PDF document text
    • https://www.reachcast.ca/wp-content/plugins/super-forms/uploads/php/files/13b33c43a977ab6a51da6c9ee0af2648/vadudorelaverofamevalev.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/q1isacrsh2qt4uq9vcd5elr0ef/vabifaxujobi.pdfIn PDF document text
    • https://ebal.ro/app/webroot/files/userfiles/files/zalosubij.pdfIn PDF document text
    • http://filatelianumismaticaumbra.it/userfiles/file/5002712397.pdfIn PDF document text
    • https://mps-india.com/userfiles/files/78753474645.pdfIn PDF document text
    • http://sarlampa.ru/upload_picture/pulazetakolugokuzi.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609eaa71ace4e---walimolomidumuju.pdfIn PDF document text
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/cfe7b376f5138ef153b1cae5b42d99b2/biroxefiwo.pdfIn PDF document text
    • http://spreewaldatelier.de/img/editor/file/lakazojerowiloxukize.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=protected+weight+bearing+meaningPDF 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_off0000ee5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE5B 10828 bytes
SHA-256: 080f7ea93225683775aad57c0cb09d77fd8ee8f38356deb2ce79d559630343ea
font_01_sfnt_off000106f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011f0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F0B 17168 bytes
SHA-256: a7f3200f0ff2ca7c626e5534151c03ac293f5c523d35e4b5a067058bb897450c