Malicious PDF — malware analysis report

Static analysis result for SHA-256 85b79feed3b25869…

MALICIOUS

PDF

72.4 KB Created: 2021-09-27 12:32:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a9522eaaa3ea88a3a192f162a0810bb4 SHA-1: 57672a53798ee9d51f470ce461b5d58b6920ab66 SHA-256: 85b79feed3b25869ef15547582b876d109f05d66984080a951a810c0615b45d2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by multiple heuristics as a link farm, with many links pointing to potentially compromised websites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document's structure and embedded URLs suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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
  • 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://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/85a12654a687f1da2f71df9731d3d522/59777850201.pdf
    • http://quatangsongvan.com/hinhanh_fckeditor/file/boxolomorepulotosuvepog.pdf
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613791aa9216f---3364572355.pdf
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/b005f6a32f8dedae76671ca23280d6d4/lifuzam.pdf
    • http://hoaisonland.vn/upload/files/tofavezapivubuv.pdf
    • http://arsvet.ru/img/upload/mowilejomilarutawedi.pdf
    • http://bulongvungtau.com/media/ftp/file/16536433604.pdf
    • http://hoanggiaphatland.com/uploads/image/files/74917105463.pdf
    • https://gmt-tw.com/app/webroot/userfiles/files/xopamo.pdf
    • http://laiksmodalux.lt/app/webroot/uploads/userfiles/files/vubad.pdf
    • http://kuhomania.ru/ckfinder/userfiles/files/98427586530.pdf
    • https://suthuytinh.com/app/webroot/uploads/files/teguki.pdf
    • http://giovanniseneca.eu/userfiles/files/fedasegisefi.pdf
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/161428883c40ee---56753167288.pdf
    • http://huzatfokozo.hu/editor_up/gujeximaxodu.pdf
    • http://duquenne-moteurs.fr/webroot/upload/files/58658036437.pdf
    • https://deltarents.com/upload/ckfinder/files/75700015220.pdf
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/222627d43f6ba5c8fbd8bebd17b705bb/fekibotamirapekuzuta.pdf
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/95b5b7c9893fba2930448312a2f52a88/xovuvenaretuno.pdf
    • http://antropolog.ru/userfiles/file/saluwobowasizupif.pdf
    • http://kartinatv.org/uploads/files/dimugaralotogipirib.pdf
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cd242eece3---24560218268.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=edjing+mix+cracked+apk
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b600.bin
5e9969ceb8d521c8a7c9ad9a40f77d1cad91480498d72552f1e15b5b21c02938
pdf-font-stream PDF embedded font (sfnt) at offset 0xB600 17704 bytes
font_01_sfnt_off0000e385.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE385 16792 bytes
font_02_sfnt_off0000fb9c.bin
2351ffa8794eedf0177239afc7ad4c717ce76949212c507f2728f9414f10c6c3
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB9C 10732 bytes