Malicious PDF — malware analysis report

Static analysis result for SHA-256 f716d5b8a042dc96…

MALICIOUS

PDF

89.7 KB Created: 2021-08-05 23:49:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: c03d5b7c58980531d113547fc464cae8 SHA-1: b2b522d0fb5af1c193f8564688e1b2041b69ba59 SHA-256: f716d5b8a042dc96525b3a39556675d29a353bd3f70f982b698b547e0ae19c70
156 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to compromised WordPress upload directories. This behavior is characteristic of a link farm used to distribute malicious content or phish for credentials. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

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 https://rubyyadav.com/nbloom/fckuploads/file/44415842705.pdf In PDF document text
    • http://cesishotel.lv/res/wysiwyg/file/17769877067.pdfIn PDF document text
    • https://tenshinorchids.com/FCKeditor_upload/file/84900241746.pdfIn PDF document text
    • http://cbcom.eu/ressource/site-image/files/63473587494.pdfIn PDF document text
    • http://fsgpj.com/upfolder/e/files/20210629030903.pdfIn PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16075e6ff68787---57289891299.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f201959db0---fesudapawupuragi.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a5d2898f64---fetokamifegi.pdfIn PDF document text
    • http://pahsclassof2005.com/clients/d/d6/d61c4c031b0f3af13d3e88110ef3a3e1/File/bataja.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607f6f25c3ccc---84071489511.pdfIn PDF document text
    • http://www.gdchgs.com/admin/img/files/xukorituxek.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/28daff0436eca3ebd1aa61b5690ec040/57696093285.pdfIn PDF document text
    • https://marwaautorepair.com/nbloom/fckuploads/file/sarefozowuxelojasosapidi.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/26698495912.pdfIn PDF document text
    • http://fields-on-earth.com/27069184577.pdfIn PDF document text
    • http://proxima-design.cz/files/file/pukoboxufexeroxuler.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/5fb5dccff8fd7d36c20dab3b2a781694/rizezalodepotezitag.pdfIn PDF document text
    • https://viveironativodevicosa.com.br/ckfinder/userfiles/files/tefejudijexujibuxizideb.pdfIn PDF document text
    • http://marmaraisg.com/images_upload/files/ruzopexurosukud.pdfIn PDF document text
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160de808f0a484---88751607505.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c60d7225dfb---15909526251.pdfIn PDF document text
    • http://thankschicken.com/uploads/files/wilaxifalujowi.pdfIn PDF document text
    • http://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/xipuzalakubamexibitisabo.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094bfa319f2d---vekekorumiwosekavero.pdfIn PDF document text
    • https://awlights.com/wp-content/plugins/super-forms/uploads/php/files/ef3e4d0f8fc098654d97c7fde2296a62/vubunusu.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9905735866---tomafafaj.pdfIn PDF document text
    • https://legacyltg.com/wp-content/plugins/super-forms/uploads/php/files/a8813972e0e6687dd34fee8ca9b795bf/37375045.pdfIn PDF document text
    • http://rosniyom.com/userfiles/files/93065322438.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=dork+diaries+13+freePDF 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_off0000fd00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD00 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011517.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11517 10416 bytes
SHA-256: f232c8df734fd83316580088ca71f5d377eb8f2a40bff91549fce80934714a3a
font_02_sfnt_off00012cdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CDB 17168 bytes
SHA-256: bc7e369b0481cd5ba82a8c7fbae9bcee3476f9e73136b05e77b9aea7ddf0816c