Malicious PDF — malware analysis report

Static analysis result for SHA-256 337aabb323bf34e9…

MALICIOUS

PDF

83.8 KB Created: 2021-09-06 15:49:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 52736363054b7cebfa684d8496258159 SHA-1: 4783e1b9685670a306e90a8991f48ff058e8269a SHA-256: 337aabb323bf34e909c140af8df31805dea65e7ee52dd9aeb48904bdf622d4ce
156 Risk Score

Malware Insights

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

The 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 compromised CMS uploads and disposable hosting. This suggests the PDF is designed to lure users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://airmon.hu/images/files/buserugujazivavuzu.pdf In PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b04cf953d77---tatodinoxubip.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607fee2a5e3a7---rokipazulopi.pdfIn PDF document text
    • https://www.tangelo.no/wp-content/plugins/formcraft/file-upload/server/content/files/1608eed2c3fe71---24852789826.pdfIn PDF document text
    • http://farmina.ru/uploads/files/72967226711.pdfIn PDF document text
    • http://alburigiott.it/userfiles/files/rikevukofozexisesa.pdfIn PDF document text
    • http://kingnature.ru/files/files/84410614866.pdfIn PDF document text
    • http://billedbutikken.dk/articlefiles/file/25408408824.pdfIn PDF document text
    • http://jullien38.com/ressource/site-image/files/davoduxavirowobirujim.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d940a29bf83---tuxazatuvokexa.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5025124ad---39466711670.pdfIn PDF document text
    • http://oilspecchem.com/files/6725961269.pdfIn PDF document text
    • http://atenngo.com/admin/sites/site/documents/47180500386.pdfIn PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/16081b8dc1b608---58328868729.pdfIn PDF document text
    • http://iwort.de/userfiles/file/68772832052.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a456f793add---ranan.pdfIn PDF document text
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160848eec1b477---27319390989.pdfIn PDF document text
    • https://cursosgratuitosonline.es/wp-content/plugins/super-forms/uploads/php/files/1mvfqnuelj25e879m7s2mikh07/nileguzedaginomawox.pdfIn PDF document text
    • http://tonioloclaudio.it/userfiles/files/88090790557.pdfIn PDF document text
    • https://slide-bearing.com/d/files/zusomotik.pdfIn PDF document text
    • https://bahispesinde.com/gnc/veri/_files/bademagifirenosuvogufe.pdfIn PDF document text
    • http://dienlanhlongan.com/upload/files/40375098015.pdfIn PDF document text
    • http://liqaa-lb.com/files/userfiles/files/vimibipame.pdfIn PDF document text
    • http://newdimension.su/userfiles/file/xiwaxumam.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=principles+of+medical+ethics+pdfPDF 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_off0000e5b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5B1 10888 bytes
SHA-256: c4400862b28406644cecc5cfe5077b247deacfac33e334d753f30e3628f8babd
font_01_sfnt_off0000fea1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEA1 16504 bytes
SHA-256: 82fe5f230d6d426702bcb03c7d5775a7ca00c2d894530495914b37311cf1b000
font_02_sfnt_off00012987.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12987 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1