Malicious PDF — malware analysis report

Static analysis result for SHA-256 d90a756f5669676b…

MALICIOUS

PDF

81.6 KB Created: 2021-09-22 14:31:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 37a5df095fbf2265bf785300c502a113 SHA-1: 5e32df26a4ee2f8331782d1795ada3ad32cbfcf3 SHA-256: d90a756f5669676bcd7122074fb252ec98ff8c50af0e172e9628c3edcf743f94
156 Risk Score

Malware Insights

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

The PDF 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 pointing to compromised CMS upload storage and disposable hosting, suggesting a phishing or malware distribution scheme. The embedded URLs, despite some being marked benign, contribute to the overall pattern of directing users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://heuresromantiques.com/upload/files/ridopiwimosenenijuwejefe.pdf In PDF document text
    • http://fotografieindex.nl/images/uploads/10009040554.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/vl2komri33e3lt68enq16jur8t/watetogifirafawogok.pdfIn PDF document text
    • http://namlinhchivietnam.net/userfiles/image/file/49066573756.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144173db0acc---tawiduvutunesaxozujagazi.pdfIn PDF document text
    • http://thietbikhachsanvinhhung1.com/upload/files/jepifuvanuxunewevalejogiw.pdfIn PDF document text
    • https://fo-prefectures.com/pages/files/finukilesonewi.pdfIn PDF document text
    • http://gurukripapublicschool.org/userfiles/file/25502767192.pdfIn PDF document text
    • http://prmakeup.com/Image/files/rototovevojolokosudifevu.pdfIn PDF document text
    • http://german-ex.com/images/blog/file/bomesi.pdfIn PDF document text
    • http://www.ecvbrass.ch/user/web/file/fodusuxisupuwefadewox.pdfIn PDF document text
    • http://iwayman.com/uploadfiles/file/210902182558887409neacwv.pdfIn PDF document text
    • http://cn-junsheng.com/upload/file///202191612995637.pdfIn PDF document text
    • http://radissonhoteltraining.com/userfiles/file/givarajakeru.pdfIn PDF document text
    • http://www.feniuniversity.edu.bd/app/webroot/ckfinder/userfiles/files/pogin.pdfIn PDF document text
    • http://aow.infogestnet.it/ckfinder/userfiles/files/7151258484.pdfIn PDF document text
    • https://stcc-sa.com/motakamel/Ups/files/bodenegigipawux.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/1614697b61f0ac---nijanudewivaviredeg.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/161476ffcdbf21---vugin.pdfIn PDF document text
    • http://thinhhoanggia.vn/Images_upload/files/jemezipapugasezasagefoj.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/uu8s07oacegvrpo2v4qvu0cokt/finiragujuponi.pdfIn PDF document text
    • https://speak82.com/_UploadFile/Images/file/xonul.pdfIn PDF document text
    • http://www.tivafa.hu/upload/file/63731412359.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=live+footbal+tv+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_off0000d7f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7F5 10236 bytes
SHA-256: 70343863709bc0ac73e9bd1753e248f8ff24f1a80ce63439734630aafa87064c
font_01_sfnt_off0000eeda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEDA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000106ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106EC 19248 bytes
SHA-256: 95a6fe81404a06be0fd53d645c81a461bcc53466a5778bb65c5329d4ef233169