Malicious PDF — malware analysis report

Static analysis result for SHA-256 322a77b741e4a290…

MALICIOUS

PDF

86.7 KB Created: 2021-09-12 05:18:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: b50664ca0d9c357f4fb88a53aab1a8d2 SHA-1: f891687d769ed1e463bc2fe24d3a1517d6180ff4 SHA-256: 322a77b741e4a2900b083547da508b292fb83a2ed0a85f594d525ff86bafe247
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to suspicious PDF files on various domains, suggesting a link farm or redirection mechanism. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further indicates a pattern of using disposable hosting for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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://zakuskymoser.cz/www/ckfinder/userfiles/files/69051068536.pdf In PDF document text
    • https://digireg.si/upload/tubapag.pdfIn PDF document text
    • http://stringladies.cz/userfiles/4217966891.pdfIn PDF document text
    • http://christmaslandint.com/userfiles/77898952088.pdfIn PDF document text
    • https://inprovituruguay.com/ckfinder/userfiles/files/wogefozu.pdfIn PDF document text
    • http://packamate.com/userfiles/82638925001.pdfIn PDF document text
    • http://tunapvietnam.thietbiotoviet.com/Images_upload/files/74674238166.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/uav7pcqsktldoevqqp38u6b74o/98392196580.pdfIn PDF document text
    • http://beautifulmoda.com/userfiles/files/bidufavuliwigireberi.pdfIn PDF document text
    • http://franklcalabreseattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jemikewifoxesevesetiluf.pdfIn PDF document text
    • http://www.ocptecnology.com/admin/uploaded/fck/file/jefajawifezobexo.pdfIn PDF document text
    • https://khambenhxahoi115.com/images/files/65967824015.pdfIn PDF document text
    • http://fsgpj.com/upfolder/e/files/20210911221521.pdfIn PDF document text
    • http://dailythang.com/userfiles/files/46375578022.pdfIn PDF document text
    • http://www.smpnuenen.nl/images/files/sigakejigivok.pdfIn PDF document text
    • https://people11people.com/uploads/File/feriwoxowitegikap.pdfIn PDF document text
    • http://ooexperience.be/assets/Image/files/45012883685.pdfIn PDF document text
    • http://emotionpicturesfestival.gr/userfiles/file/74117041129.pdfIn PDF document text
    • http://toszegisuli.hu/userfiles/file/runopinezitosedirogibiri.pdfIn PDF document text
    • http://aesg2edcv.handylover.com/upload/files/88513568262.pdfIn PDF document text
    • http://tincorner.vn/uploads/files/kudifudalamulaxumusari.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136410be818e---99534743606.pdfIn PDF document text
    • https://tmtteks.com/files/xamopesapajezamofo.pdfIn PDF document text
    • http://dwornawodzie.pl/userfiles/file/18631397484.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=tubemate+online+for+pcPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ccda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCDA 22076 bytes
SHA-256: f9aaa885bec0b5534a76d4c2806e8a66a171c555949792240c04adc455dd96ca
font_01_sfnt_off000106dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106DC 16232 bytes
SHA-256: e06ebeaa2bb94d9bf14337b0794fec2c9c4a66e30291689b6f6234bfe360c8a5
font_02_sfnt_off00011cbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CBF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off000134d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134D6 10676 bytes
SHA-256: 79df52fdc3c0d5c7f8249604d983c18efe07cc4323965337d7d68e506d2f9d49