Malicious PDF — malware analysis report

Static analysis result for SHA-256 92a20805770b3f79…

MALICIOUS

PDF

80.8 KB Created: 2021-09-21 06:15:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7f6a917d4ecc8ca51f81e2061bf2a88d SHA-1: 187203d9ca91296e28859ec65ba29682d4694c8f SHA-256: 92a20805770b3f79a546efcdc34310d14df17df75e2dade0f31564452c732b6c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF contains embedded JavaScript, which is often used to redirect users to malicious websites. The numerous external URIs, including links to compromised WordPress sites and link farms on disposable hosting, strongly indicate a phishing or malware distribution attempt. The ML classifier and ClamAV detection further confirm its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • 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.
  • 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://synerhu.ru/uplcv?utm_term=picture+too+big+for+wallpaper+android PDF link annotation
    • http://www.ramseier-appenzell.ch/elrada/js/ckfinder/userfiles/files/42426972294.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135c9d310cdd---22044931013.pdfIn PDF document text
    • http://nhatnamvina.vn/rich_editor/file/jasawevidopirikizigok.pdfIn PDF document text
    • https://hargagila.com/uploads/image/files/fupazugizizufidekirijoke.pdfIn PDF document text
    • https://mywayrtk.com/userfiles/file/zafenawowuz.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/11791984507.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132e3904b824---1420395280.pdfIn PDF document text
    • http://okna-kursk.ru/page_edit/_samples/userfiles/files/pefuzobepubivagux.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/kusipepabovirorunovodan.pdfIn PDF document text
    • http://7profi.net/userfiles/file/jolibodesulejojisosufi.pdfIn PDF document text
    • http://chandigarhdatarecovery.com/files/file/85111189054.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/161352c87e7ff3---48115764574.pdfIn PDF document text
    • https://syteq-pro.com/userfiles/file/50491831464.pdfIn PDF document text
    • https://www.fyna.com.au/application/third_party/ckfinder/userfiles/files/kokin.pdfIn PDF document text
    • https://vresponse.net/userfiles/file/2903623863.pdfIn PDF document text
    • http://nuklearmedizin-amro.de/userfiles/file/sosilulixisef.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/16130dedb7bbf4---84712833046.pdfIn PDF document text
    • http://jcon-aps.dk/userfiles/file/lavozopet.pdfIn PDF document text
    • http://dydlhx.com/upfiles/file///pokisonid.pdfIn PDF document text
    • https://riwg.in/userfiles/file/94241300794.pdfIn PDF document text
    • http://chinalabware.es/d/files/moxiguwefuni.pdfIn PDF document text
    • https://chilegastronomia.cl/uploads/userfiles/files/74885643235.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_off0000d807.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD807 10952 bytes
SHA-256: 7533ad33266152d22c75467fc019eb4fff1ac1079f301b2ce465a4dbd81dc2a5
font_01_sfnt_off0000f12f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF12F 17052 bytes
SHA-256: cc489d5ddbc453c604b38e8fff77ee8623056a4899656d9955fa9630ab0938fb
font_02_sfnt_off00011d80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D80 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1