Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f8911f6dd9566a8…

MALICIOUS

PDF

80.9 KB Created: 2021-09-18 06:35:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 88ae9ada21dd55c2b8541c8c2516ab6c SHA-1: 4f5d49460d5e1e324315c61ab855051553f943c2 SHA-256: 8f8911f6dd9566a85eccd19bb6111f9854c6e1f6727568ab3853beabc734bf12
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF containing a link farm, with multiple heuristics indicating it is designed to host or redirect to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and embedded URLs point towards an attempt to trick users into downloading further malicious payloads.

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://irlanc.ru/uplcv?utm_term=outlook+android+exchange+setup PDF link annotation
    • http://gazetavk.ru/img/file/33157303102.pdfIn PDF document text
    • https://ewt.cz/res/file/39337934709.pdfIn PDF document text
    • https://xn----7sbbg1ddpkdc.xn--j1amh/uploads/files/84564948316.pdfIn PDF document text
    • http://cwesp.biz/upload/file/3540560240.pdfIn PDF document text
    • https://cian.hr/userfiles/file/mipuga.pdfIn PDF document text
    • http://gomsuhoangminh.com/app/webroot/uploads/files/26627490168.pdfIn PDF document text
    • https://saintarseny.ca/sites/saintarseny.ca/files/file/fanulipivenogo.pdfIn PDF document text
    • http://arcos-eff.it/userfiles/files/lodaz.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/161361edd1a783---fojasejiwipowomirawazo.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dfc3563ed3---tozawakogo.pdfIn PDF document text
    • http://evola.it/userfiles/files/jizasekegugolu.pdfIn PDF document text
    • https://hotelite.in/userfiles/file/zutizawonike.pdfIn PDF document text
    • http://floridadressyourhome.com/uploaded_files/userfiles/files/56776577030.pdfIn PDF document text
    • http://tcihk.com/userfiles/46428787577.pdfIn PDF document text
    • http://kaushalacademy.org/ckfinder/userfiles/files/15790494799.pdfIn PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134055584801---zuwoxora.pdfIn PDF document text
    • http://acelybio.com/upload/files/xikebefapojalifemavivose.pdfIn PDF document text
    • https://academiapreprod.riportico.com/userfiles/files/22105863215.pdfIn PDF document text
    • https://shivajigrihnirman.com/singhania/downloads/file/wefifetixe.pdfIn PDF document text
    • http://trumoi-khutrung.com/upload/files/fusigimu.pdfIn PDF document text
    • https://alate.org/admin/fckeditor/editorfile/bijonowowudogojewekuwobed.pdfIn PDF document text
    • http://nuovartea.eu/userfiles/files/gerudoxi.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_off0000d4c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4C5 11112 bytes
SHA-256: 6862b60dd9aad0541f512730c811862b9fec342bc9562fb80707f46523dd8c09
font_01_sfnt_off0000ee79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE79 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001068b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1068B 18284 bytes
SHA-256: b538915b6c8c988a345a5dd362d72519f274a029a69e1a3f303826e16e982237