Malicious PDF — malware analysis report

Static analysis result for SHA-256 3987d87c36f51490…

MALICIOUS

PDF

89.9 KB Created: 2021-07-31 15:52:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 040ca6cab460a81d1c17ab20bd361bad SHA-1: 7e71903c47cbed2d3dd2ca25d7ca170350dede5e SHA-256: 3987d87c36f514904dd7fa6eb135ef4d79e939bb29ef0bff493c311e61d931d2
164 Risk Score

Malware Insights

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

This PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan payload. It contains numerous links, many hosted on compromised CMS upload directories, designed to lead the user to download further malicious content. The presence of a 'download button' heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://rijst.nu/userfiles/file/5648055387.pdf In PDF document text
    • https://satuldelut.ro/ckfinder/userfiles/files/jaxomow.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdbfc506d2c---15446575973.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/76d11v4kk24a075i5a939cm082/48323663562.pdfIn PDF document text
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/b5112b20fdbe4c8f6be778437f5caef6/tisaliruzaxafidupuwidor.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/ap378r929jluc3j89vm97k5tr1/40573334060.pdfIn PDF document text
    • http://inimtrento.it/userfiles/files/zukewirogijanidatozuxa.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/c244970824261c60b1e3922021143d75/kimiwarudasatereso.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/iagqasgdk454huq71n2hj3hobf/97986330506.pdfIn PDF document text
    • http://capitalclassof1971.com/clients/4/4c/4c1e4f015ba9b8bec237dc1ca705466d/File/gogajekunudurataw.pdfIn PDF document text
    • http://silesiacapital.eu/data/file/nelavamidideka.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/f03754c4389670dbed324e55782dab8f/wutexuzedurizegu.pdfIn PDF document text
    • http://qualityspices.in/ckuploads/files/lakul.pdfIn PDF document text
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/8g9dv9i2h76h1ln9d3p3iuss7a/70721219011.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ec3e9a132fb---zanedojes.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606eac4bca40d---85721475547.pdfIn PDF document text
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/e21137db7039100512836e72b7e44ad3/wivuvukizakamumop.pdfIn PDF document text
    • http://oilmachineydy.com/d/files/45494205968.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b779bc0791c---15110438688.pdfIn PDF document text
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085415481de3---zisuvibuvukuserixofutari.pdfIn PDF document text
    • http://lblussana.it/images/file/vasanevasuk.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160acebae74dea---xanobeverupunomagirowixeb.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=tm-ac1900+merlin+384.6PDF 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_off0000f8bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8BB 11036 bytes
SHA-256: 5e18bf06417fb347b405230ab84246b67fe3bca331933c15025e3502c47dfbf4
font_01_sfnt_off00011265.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11265 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012a77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A77 18132 bytes
SHA-256: 311f4bf74d6dbf8b52791ce58d5692aa32a8b8e144a7dd5563a637e5e30bbbe7