Malicious PDF — malware analysis report

Static analysis result for SHA-256 78b9ac51cc797fc5…

MALICIOUS

PDF

68.7 KB Created: 2021-09-11 10:10:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d62b2b89a405d67471fc42e21ff78c7e SHA-1: b1a84bbdbc8706b68c0c33f641ea7df028309d14 SHA-256: 78b9ac51cc797fc5ad027b4dd6b4a3915dea38aa2195d0677605b7bd1fd08d9c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which are hosted on potentially disposable domains, suggesting a link farm or phishing lure. The PDF structure and embedded content, despite being heavily obfuscated, point towards an attempt to redirect users to external, untrusted sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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 http://cuanhuadanang.vn/uploads/image/files/vifukuxigolomobepoja.pdf In PDF document text
    • https://fobh.net/userfiles/files/nevukenumefopiropag.pdfIn PDF document text
    • http://agecarekorea.com/ckupload/files/22477105230.pdfIn PDF document text
    • https://kompaspt1.com/contents/files/wafakutule.pdfIn PDF document text
    • http://artospace.com/pics/file/bivivoxewavilumerugepepet.pdfIn PDF document text
    • http://vincitydata.com/uploads/ckfinder/files/povagefirudojazetavot.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/cfb1cdccc0acfe4da2f65e78f668ce0d/12688807507.pdfIn PDF document text
    • http://serramentisiciliano.it/userfiles/files/54599599850.pdfIn PDF document text
    • http://coomargroup.com/ckfinder/userfiles/files/65299555595.pdfIn PDF document text
    • http://newcityhk.com/userfiles/6179068346.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/16135d28202949---viwozizepewepigog.pdfIn PDF document text
    • http://swatimishra.in/uploaded_files/userfiles/files/wazami.pdfIn PDF document text
    • https://mk-sito.it/uploads/file/mutasebojazes.pdfIn PDF document text
    • http://em-mould.com/ckfinder/userfiles/files/gezubododowitegovufajutij.pdfIn PDF document text
    • http://longthinhphat.net/uploads/files/23968044709.pdfIn PDF document text
    • http://pillshop.ru/uimg/files/tenitiw.pdfIn PDF document text
    • http://vivaibonomo.it/userfiles/files/34994732920.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/58637057875.pdfIn PDF document text
    • http://kprmk.pl/userfiles/file/71126178770.pdfIn PDF document text
    • http://zhuxintrading.com/uploads/ckfinder/files/20210908/16310761375724.pdfIn PDF document text
    • http://zaragozalawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/rokinerugit.pdfIn PDF document text
    • https://stratasphere.online/userfiles/file/guzawipusujexegif.pdfIn PDF document text
    • http://ztkammer.at/uploads/file/86030961161.pdfIn PDF document text
    • http://sictombbi.fr/ckfinder/userfiles/files/tijupovusetiwitulanorejil.pdfIn PDF document text
    • http://vzwsportenmuziek.com/content_docs/75646946405.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=dreame+unlimited+coins+hack+androidPDF 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_off0000b000.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB000 14840 bytes
SHA-256: f0790852e150d974d4e76c99b36d8b2af7edf2c682935790f94d51dc3e60e84a
font_01_sfnt_off0000d450.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD450 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ec67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC67 10828 bytes
SHA-256: c14472ff009a3d405b2dc4c386db80485b5c24906b224c66f74868372b5b7076