Malicious PDF — malware analysis report

Static analysis result for SHA-256 8911906349f82c9c…

MALICIOUS

PDF

69.9 KB Created: 2021-09-24 21:02:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: 37c98b9afa782d19b3d2c10274fc4f59 SHA-1: 5f570e04ee333a1cac34e1b369e27609632091c6 SHA-256: 8911906349f82c9c7b3bf98e080e3c07d22e8e4a33dce7b92e851932de0cf4a8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://coretry.ru/uplcv?utm_term=free+install+tubemate+for+pc PDF link annotation
    • http://www.ecostroyservis.ru/File/pizujodobepudugup.pdfIn PDF document text
    • http://targhevaticane.it/userfiles/files/rusimevofanuzewewukelamo.pdfIn PDF document text
    • https://radekslodkiewicz.pl/files/file/61330235740.pdfIn PDF document text
    • https://larustt.com/upload/ckfinder/files/83736079380.pdfIn PDF document text
    • http://zussobrance.sk/grafika/dokumenty/lodatine.pdfIn PDF document text
    • https://dukeofmarshall.com/ckfinder/userfiles/files/zonuniditi.pdfIn PDF document text
    • https://southernwashpros.com/nbloom/fckuploads/file/62755707986.pdfIn PDF document text
    • http://menifee.hanasushichoice.com/uploads/files/bajuzobulujawirelalu.pdfIn PDF document text
    • http://www.moyekolodin.com/files/73184644743.pdfIn PDF document text
    • https://fenicia.uy/fenicia.com.uy/uploads/files/ridurako.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613214506a9a0---70207888320.pdfIn PDF document text
    • http://ty-universe.com/image/files/20210902_043124.pdfIn PDF document text
    • https://sieuthigo.vn/upload/ck/files/nawiwusat.pdfIn PDF document text
    • http://nieruchomosci-swidnica.pl/userfiles/file/memenamebefenebenonafuduk.pdfIn PDF document text
    • https://edusfera.pl/upload/file/32734449688.pdfIn PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d4a3242e1c---sizifugunogakenaf.pdfIn PDF document text
    • https://jagamimpi.com/contents/files/983419018.pdfIn PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16136d9e4159a9---pokobimasi.pdfIn PDF document text
    • http://cathugo-catamarans.de/res/wysiwyg/file/wivowox.pdfIn PDF document text
    • http://caraudioshop.ro/mm/file/kagifudu.pdfIn PDF document text
    • https://hobbyschuurtje-webwinkel.be/images/userfiles/file/lotabuweradimovewujifesup.pdfIn PDF document text
    • http://stagelight.pl/userfiles/files/90675265810.pdfIn PDF document text
    • http://studioindelicato.com/userfiles/files/98582410473.pdfIn PDF document text
    • http://tizianaiberti.it/userfiles/files/nalejumafulifumodidubivi.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_off0000b1ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1AD 14932 bytes
SHA-256: 186f9c1c52c236452490d54d4a03980ce897c3d3c090acdf8028cee33528cfbc
font_01_sfnt_off0000d71f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD71F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ef36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF36 10860 bytes
SHA-256: 791ecd03c6e5a73d4499344b0d3928cc97192ef13414adf713135dfc262e18ce