Malicious PDF — malware analysis report

Static analysis result for SHA-256 83bcf211f46b2f2d…

MALICIOUS

PDF

73.3 KB Created: 2021-09-09 19:36:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 21d7e3de25dbadf1b39abf1c21ad5c3e SHA-1: 95f652fadf5c569ef4f86ae6e29d5be325201880 SHA-256: 83bcf211f46b2f2db0ffc83c4c465483aa498b6a73dfa47bee0d086f065357e0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV, indicating malicious intent. The presence of numerous external URIs, many pointing to disposable hosting and utilizing UTM parameters, strongly suggests a phishing or malware distribution campaign. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically identifies the document as a link farm designed to obscure its true purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9915

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://oniceh.ru/uplcv?utm_term=pdisk+movie+app PDF link annotation
    • https://nomortiga.com/contents/files/85210093692.pdfIn PDF document text
    • http://viethanit.vn/hinhanh/file/madujixoworuzikebix.pdfIn PDF document text
    • http://luisacortesearchitetto.it/userfiles/files/sitirufovenodiwemiranu.pdfIn PDF document text
    • http://cuatro-pr.org/sites/default/files/file/telarunakutewusofogebadi.pdfIn PDF document text
    • https://investir-petroleo.pt/ckfinder/userfiles/files/bikuwapura.pdfIn PDF document text
    • https://giraffeng.net/infodaily/gen-ckfinder/userfiles/files/xupirawififodugenusu.pdfIn PDF document text
    • https://hohsingfiber.com/ufiles/files/vumoxulegaladijatevilusa.pdfIn PDF document text
    • https://network-italia.it/file/27736089212.pdfIn PDF document text
    • http://nhatrangpalacehotel.com/app/webroot/upload/files/gisujax.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1613a26f956f30---tokirot.pdfIn PDF document text
    • http://mascotdd.com/file_media/file_image/file/dalidozununopewol.pdfIn PDF document text
    • https://umutfm.com/resimler/files/42288824900.pdfIn PDF document text
    • http://macautemple.com/userfiles/file/juloj.pdfIn PDF document text
    • https://invision.buzyhub.com/files/25598978905.pdfIn PDF document text
    • http://tmkb.org.tr/ckfinder/userfiles/files/zilux.pdfIn PDF document text
    • http://aftp.bg/userfiles/file/709213300.pdfIn PDF document text
    • https://408of53crownstreet.com/assets/media/files/pupugularudupomofofogimun.pdfIn PDF document text
    • http://www.morrisjones.co.uk/EditorImages/file/73657096587.pdfIn PDF document text
    • http://ps-chiptuning.hu/userfiles/files/fawefababudusuf.pdfIn PDF document text
    • http://t-p-fortune.com/userfiles/file/70852962843.pdfIn PDF document text
    • https://nhahangthanghuong.com/uploads/files/53054611653.pdfIn PDF document text
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/7d17e3a5d35c0f44024cf5326ccc50d9/savelivif.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/monipagufedulotevib.pdfIn PDF document text
    • https://navoloki.mebel18.com/uploads/files/67010205980.pdfIn PDF document text
    • https://serwisnawigacji.pl/userfiles/file/41398370048.pdfIn PDF document text
    • http://tiszaikaland.hu/upload/file/luvunubifiwanodasi.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_off0000bbbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBBD 16688 bytes
SHA-256: 65dd11b34722614efcea0ab4b97e01c37e0040a46130dcd72c13db3221d0ebb4
font_01_sfnt_off0000e6a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6A3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000feba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEBA 10364 bytes
SHA-256: a839c29a567cdd634f88bd936a56593f680a1ac013e0402b906460c32795d17b