Malicious PDF — malware analysis report

Static analysis result for SHA-256 423f3f244660cc40…

MALICIOUS

PDF

85.3 KB Created: 2021-09-13 16:11:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: cf90963c00bef4bf6bb31d09a96199e4 SHA-1: 30c04903db7c4e3a61a58aed8cde5ef8a1d54894 SHA-256: 423f3f244660cc409b70a0248d568d99c501b9804bf30ef212916514773dcb8a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. It contains numerous embedded URLs, many pointing to disposable domains, suggesting a link farm designed to redirect users to potentially malicious content. The presence of external URIs and the 'link farm' heuristic strongly suggest a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://allytemp.ru/uplcv?utm_term=watch+live+football+on+android+phone PDF link annotation
    • http://chiangmai-esc.net/user_img/files/86435759858.pdfIn PDF document text
    • http://profstil.az/userfiles/file/83407113564.pdfIn PDF document text
    • https://njshore.drinkpoint.com/uploads/files/gikev.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130033690539---91539785175.pdfIn PDF document text
    • http://tygodnikzuzlowy.pl/ckfinder/userfiles/files/tenuwiwetulekujab.pdfIn PDF document text
    • https://hilanguage-com-tw.triangle-design.com/files/regazelisudibur.pdfIn PDF document text
    • http://rymwid-training.com/userfiles/file/7388278405.pdfIn PDF document text
    • http://rc-modeller.se/images/file///22948002020.pdfIn PDF document text
    • http://naturestuff.nl/siteimages/file/21388623431.pdfIn PDF document text
    • http://theartofdesign.nl/ckfinder/userfiles/files/kajizu.pdfIn PDF document text
    • http://bm-shower.com/userfiles/files/zomitevigodanenelari.pdfIn PDF document text
    • http://app0.linkeo.it/ckfinder/userfiles/files/sukozi.pdfIn PDF document text
    • https://escolaalfa.com/userfiles/file/8854909648.pdfIn PDF document text
    • http://aeklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kovixofozeviditifekiw.pdfIn PDF document text
    • https://vinaarc.com/app/webroot/files/ckfinder/userfiles/files/wolilujujebesijer.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/f5f29e48e167d57fd3df81d12b8aa524/87188926696.pdfIn PDF document text
    • https://webmenuplus.com/images/file/tofojolepenivuvumirasaw.pdfIn PDF document text
    • http://altiro.nl/home/tjerk/file/2705633028.pdfIn PDF document text
    • http://fruhmann-elektrotechnik.at/moretuvapibutozubaliga.pdfIn PDF document text
    • http://oprandi.it/userfiles/files/sabolofiruvumelu.pdfIn PDF document text
    • http://duquenne-moteurs.fr/webroot/upload/files/66467264347.pdfIn PDF document text
    • http://investinwielkopolska.pl/application/lib/ckfinder/userfiles/files/3392926791.pdfIn PDF document text
    • http://dailymaydemtien.com/userfiles/files/givegeva.pdfIn PDF document text
    • http://americandeliorder.com/uploads/files/nixasuvibaseti.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_off0000e6e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6E5 10748 bytes
SHA-256: 5c668ade1e188c2eb9298de6695b354ccfc00231856861ce7eee5e467b5a88b9
font_01_sfnt_off0000ff54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF54 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011766.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11766 18352 bytes
SHA-256: 5b0aee1795fda74bee3f2d2ce618568bf1af4f1cec4cec128157f3e21edbdc9e