Malicious PDF — malware analysis report

Static analysis result for SHA-256 135bcff5448140cc…

MALICIOUS

PDF

79.7 KB Created: 2021-09-02 10:57:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 85e7586c7fdcbc1f711e01d684a26e48 SHA-1: c79c1528499e1c9b7320a88485003fd7e0d83b58 SHA-256: 135bcff5448140cc4412c36f7926310698904801e5614ec02b99baad0c240a8a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically identified as a phishing trojan. Heuristics indicate it functions as a link farm, pointing to numerous URLs hosted on potentially compromised or disposable domains. The embedded URLs are designed to redirect users to external sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://gpsputhuppally.com/userfiles/file/39605236453.pdf In PDF document text
    • http://www.siscbolivia.com/admin/uploaded/fck/file/5175072687.pdfIn PDF document text
    • http://sportingfoundation.com/uploads/file/muponume.pdfIn PDF document text
    • http://intimatehotelpattaya.com/image/upload/File/17850709234.pdfIn PDF document text
    • https://pacie.vn/web/uploads/files/90581385335.pdfIn PDF document text
    • http://cityhelps.org/clients/6/61/61afa7a028a8e04f14432b0fece6f2b0/File/pulaj.pdfIn PDF document text
    • http://thietbiotovn.com/Images_upload/files/vupefagiraxivo.pdfIn PDF document text
    • http://serbanindustrialconstruct.ro/uploads/files/44982020329.pdfIn PDF document text
    • https://islandsvefir.is/wp-content/plugins/super-forms/uploads/php/files/vklpb0p4e6f6age2jt1lpid0r8/20913155512.pdfIn PDF document text
    • http://hayatteknoloji.com/webimage/file/40204952963.pdfIn PDF document text
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/e790b0936ff6406108da3f179711d009/17318850548.pdfIn PDF document text
    • https://braus.uz/images/shared/file/pefuratopijenoxatu.pdfIn PDF document text
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/af65b3da160aca8ea5dcec1ab9a91ead/88188286543.pdfIn PDF document text
    • http://allaboutdowney.com/userimages/norujesejuz.pdfIn PDF document text
    • http://dalnoboy.net/data/filestorage/upload/files/novuj.pdfIn PDF document text
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/129bua4i9u04h3h5pmbodein0d/tubuminupiv.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/07a0e4cdc21ab0cbca42ebf85d110b7a/87171154949.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160965c1be29f7---3124410216.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/160bd59a46126d---xukamosibiguvobeviga.pdfIn PDF document text
    • http://ypdtools.com/ckfinder/images_store/files/31885706780.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=formal+introduction+of+yourselfPDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d58f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD58F 16648 bytes
SHA-256: 8bf6ec9cb5f58cf26bc6b9bf3e528d7915e957acef3be62894397785ce9ec993
font_01_sfnt_off000100d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000118ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118EC 10828 bytes
SHA-256: 95ede00701851935f2e0069e43fd94478b0f33eea1426b8a1d35d98ec44ca5fa