Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3849e7115947a3a…

MALICIOUS

PDF

87.0 KB Created: 2021-07-22 12:18:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f20714f2559e37382c7d729acc5acb7b SHA-1: b979688d99295eb48f622e3764984c2ca4f61f60 SHA-256: e3849e7115947a3a18f49034fe0f9f26d03ce0129b6772250c13209c831b61d0
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious content or phishing pages. No scripts were extracted, and the document body was unreadable, limiting further analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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 http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a30daa7a6b0---fakifijetinofemulib.pdf In PDF document text
    • http://extracam.es/app/webroot/arxius/file/72021187602.pdfIn PDF document text
    • https://presstone.hu/userfiles/file/60656863888.pdfIn PDF document text
    • https://vildmarksjagt.dk/userfiles/file/33263797689.pdfIn PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a68d868c3ad---9386877622.pdfIn PDF document text
    • http://autobedrijvenindex.nl/images/uploads/1818904483.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607da20ebd25c---35119179754.pdfIn PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606d26ec20074---1494753944.pdfIn PDF document text
    • http://ophirtonhotel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160dfa31a67cd4---teziveguwewapiwopama.pdfIn PDF document text
    • http://kythuatviet.vn/uploads/userfiles/file/lukilakedole.pdfIn PDF document text
    • https://deniz-sogutma.org/img/userfiles/file/13376758558.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/saoeckbsk9oib7g9s0kof2p7sv/15561880871.pdfIn PDF document text
    • http://indecomavo.pl/inc/likajov.pdfIn PDF document text
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/c1lnlph6a7hpm2u257qh1c9nr7/fasido.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/jnl35ardh0e2f672bsqsi01aqt/11453879426.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16079e24fac937---78569507403.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/1607dc48a465fe---20456229098.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092b54834c6e---29048779317.pdfIn PDF document text
    • http://www.microsinusectomi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f4cd01d60e---ludodugojilironipasudafib.pdfIn PDF document text
    • http://sys-svinding.dk/userfiles/file/16683198241.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/c127d7219a72fd2acc15a528f7f7509f/naxolodifufijikekubi.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/ruvuvemetijajos.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a441fa09d40---6490668149.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1609421bae827a---xitukogebozulo.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/d78ff3c1cc9d1a32d42315bcb60d1b9c/gimisig.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/160823abfebeb6---pejolopuvuv.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca66bdbf54---xixevupajesapewe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=the+sound+at+the+end+of+endgamePDF 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_off0000f114.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF114 10624 bytes
SHA-256: 0530d6feb977e50ac8339c12bf307081c00e585227cb7931b9270f9931c10fca
font_01_sfnt_off00010903.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10903 17148 bytes
SHA-256: 8afca76edec2f70f67bd7ca658f8fdad98fb0ec9ff84d215a200303f8b3be2ca
font_02_sfnt_off000135fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135FE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1