Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec5d9c6dbe73b3e7…

MALICIOUS

PDF

79.0 KB Created: 2021-09-18 10:53:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7936252dde5542a37b27f80c2c224e09 SHA-1: 435a06533d33b164d85ac8b808a0030dcd1cae16 SHA-256: ec5d9c6dbe73b3e76f11de4c6076c94e0776ac2b1e49441cc7ede5f6383debeb
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, with high confidence. It contains embedded JavaScript and numerous external URIs, indicating it likely attempts to redirect users to malicious websites for phishing or to download further payloads. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests a tactic of using many disposable domains to obscure the true malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://crewmak.ru/uplcv?utm_term=battery+calibration+repair+apk PDF link annotation
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140764885447---38808284255.pdfIn PDF document text
    • http://m-styleauto.com/js/upload/files/98152406560.pdfIn PDF document text
    • http://perechen-jurnalov.ru/js/ckfinder/userfiles/files/bejuduwilixabam.pdfIn PDF document text
    • https://burragebrothers.com/demo/jolie/beta/userfiles/files/vifukofako.pdfIn PDF document text
    • http://jandenzobv.com/image_uploads/file/xumawefarisokaxijikatu.pdfIn PDF document text
    • https://parc-hotel.info/file/99122981389.pdfIn PDF document text
    • http://el-system.jp/uploads/2012/files/bixetarovunifa.pdfIn PDF document text
    • https://allora-tour.by/var/upload/file/kirisebalekojadiberab.pdfIn PDF document text
    • http://85560891.com/upfolder/e/files/20210902124705.pdfIn PDF document text
    • https://sapporomn.com/userfiles/files/69512995692.pdfIn PDF document text
    • http://w.scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/mafoxinibelonopej.pdfIn PDF document text
    • http://cl-metalparts.com/d/files/maturazevasepa.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161457e1cd0e47---zudefetigadupisisis.pdfIn PDF document text
    • https://isitekmuhendislik.com/userfiles/file/45376761246.pdfIn PDF document text
    • https://chameleoncoupons.com/adgprocessing/uploads/files/96900069952.pdfIn PDF document text
    • http://kleiberit.ru/files/file/runow.pdfIn PDF document text
    • http://hoclaixebinhthuan.com/upload/contentFile/file/98637780439.pdfIn PDF document text
    • https://efnnma.org/files/file/48715139902.pdfIn PDF document text
    • http://townofwinslowin.com/flash/townofwinslowin.com/file/16781587299.pdfIn PDF document text
    • http://alkanboya.com/files/file///kiteweberatazezuri.pdfIn PDF document text
    • http://pm-ural.com/uploads/files/kexujizepal.pdfIn PDF document text
    • http://hansungid.com/userfiles/file/4794565951.pdfIn PDF document text
    • http://taxplus.in/images/contentimages/files/36620084350.pdfIn PDF document text
    • https://peltonfell.org.uk/ckfinder/userfiles/files/fevexuzoxutabolira.pdfIn PDF document text
    • http://tk-weld.com/images/library/File/gudufuwineteka.pdfIn PDF document text
    • https://izometal.net/mm/file/rezimug.pdfIn PDF document text
    • https://easyown.ddproperty.com/datas/files/sedajekazopajiri.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_off0000cfc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFC2 10600 bytes
SHA-256: 84b5f31c8f1a4971e003dad92496382c9a26576b2f8f6f1db749b3ee36592128
font_01_sfnt_off0000e7e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7E6 17760 bytes
SHA-256: 63553b38cf697c78d728943f8bacd2d4673de73760fa95fd2c5a94aeb3414c86
font_02_sfnt_off0001169f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1169F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1