Malicious PDF — malware analysis report

Static analysis result for SHA-256 f054607ba8edf3a5…

MALICIOUS

PDF

81.4 KB Created: 2021-09-21 16:26:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 962ca062e4e0db4bb2612ebbe9b5f677 SHA-1: c97a5c8885c4033d9339b87272eb9caf07694979 SHA-256: f054607ba8edf3a51df5e23b85a6f7484f9f67ed42ca23e62cb8859a300f4066
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of embedded URLs, many pointing to disposable domains or compromised CMS upload directories, indicating a link farm designed for malicious redirection. ClamAV detected this as a phishing trojan, and the ML classifier also flagged it as malicious. The primary attack pattern observed is the use of a link farm to lure users to external malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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 http://bluebossa.pl/files/file/12302976380.pdf In PDF document text
    • https://dangeloremodeling.com/nbloom/fckuploads/file/32382854885.pdfIn PDF document text
    • http://dlastudenta.org/Upload/file/puzidutonibel.pdfIn PDF document text
    • http://nwatchonline.net/userfiles/file/85003319824.pdfIn PDF document text
    • http://inhome360.ru/admin/ckfinder/userfiles/files/10355551839.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/c22f6db169de0cdcc581b23cb093386d/sudemixozaruxajusikigara.pdfIn PDF document text
    • https://retrofitoman.com/ckfinder/userfiles/files/68273073121.pdfIn PDF document text
    • http://mirsistem.com/depo/sayfaresim/file/suxaradulazu.pdfIn PDF document text
    • http://rasciindia.com/firetech/ckupload/files/46380821816.pdfIn PDF document text
    • http://gzperson.com/uploadfile/files/gosabuminuboxafe.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/0e85e44f6996ee26f557b7e8a4afe69b/49280335671.pdfIn PDF document text
    • https://angkaganjil.com/contents/files/loroxa.pdfIn PDF document text
    • https://opsclown.it/ckfinder/userfiles/files/93024043466.pdfIn PDF document text
    • http://cesarrodarte.com/userfiles/file/72263607396.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/16iudv7l19235lh7d5raa71ibn/78429103798.pdfIn PDF document text
    • http://majedalkarkhi.com/pics/file/jurirojuxa.pdfIn PDF document text
    • http://haphadoor.com/upload/files/ripenine.pdfIn PDF document text
    • http://studiotecnicopinto.it/userfiles/files/92921891955.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613f057d99b18---7693169178.pdfIn PDF document text
    • http://benthanhsgfarm.com/images/uploads/files/tenemufetixiwo.pdfIn PDF document text
    • http://studiomuraca.eu/userfiles/files/feterujufesujefenoni.pdfIn PDF document text
    • https://dintek.eu/uploads/file/murerinenatupepuxi.pdfIn PDF document text
    • http://www.rarlaw.net/siteuploads/editorimg/file/jetovaziriti.pdfIn PDF document text
    • http://smirna.pl/files/file/mikulaxirajelubemita.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/16146d631e7b4d---kidedifagatutidefavanat.pdfIn PDF document text
    • https://djecijagarderoba.me/userfiles/file/wamawonubirinopitupamija.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=logo+maker+mod+apkPDF 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_off0000dc20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC20 10276 bytes
SHA-256: d4b2a4a224734e9cff197d961db636a8907f9837ad98f0f72df08086217f8df2
font_01_sfnt_off0000f305.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF305 17336 bytes
SHA-256: ea6b25d21ad069ad419948a8ee46ebad15a966ec83d648ff3d20deea9102996c
font_02_sfnt_off00012014.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12014 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1