Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6c019df2fd576af…

MALICIOUS

PDF

91.5 KB Created: 2021-06-27 22:58:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 1d1dcdc7bf69f9ec2626fffc75676204 SHA-1: c69ce49c727c2645e331e4590d55eaf0be79d835 SHA-256: a6c019df2fd576af9a273b56ac070826631768f229cfc633b75dd40ef0a2801a
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised websites hosting further PDF files. This suggests a multi-stage attack, likely for phishing or distributing additional malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://archism.ru/uplcv?utm_term=baby+hiccups+when+feeding PDF link annotation
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/1b0607513fe6f5f4d55bee7190007400/didowukut.pdfIn PDF document text
    • http://tulsamemorialclassof71.com/clients/84987/File/tiseb.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/160a59dddc7e00---59968295714.pdfIn PDF document text
    • http://eotp.info/sites/default/files/fck/file/86435620024.pdfIn PDF document text
    • http://cs-golfclub.com/ckupload/files/gofimu.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf4b779182---nirujerubajetomimuxuva.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088a89873900---31130867543.pdfIn PDF document text
    • https://wills.sg/wp-content/plugins/super-forms/uploads/php/files/b9d31ac3a983ef5f8459d6e3b447fb64/82980037487.pdfIn PDF document text
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cc3bf54471---venigedegadu.pdfIn PDF document text
    • https://www.escon.it/wp-content/plugins/super-forms/uploads/php/files/1ec30b314f0bb199bd65b8672e0af63d/32912986858.pdfIn PDF document text
    • https://beyondpins.com/calisma2/files/uploads/36934024401.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8374a5b7c3---pupado.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160d336fa5ce0d---12525999076.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/160983db32b2aa---budufifu.pdfIn PDF document text
    • http://narnivet.com/userfiles/files/narujiles.pdfIn PDF document text
    • https://edu-mate.kr/_UploadFile/Images/file/25941503720.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090efc090530---bafetebo.pdfIn PDF document text
    • http://www.victoriousintl.com/new/resource/files/fazevenodikavo.pdfIn PDF document text
    • https://cowichanseniors.ca/userfiles/file/mojonozukan.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/m9nq7ej2eqkumlutjh734t7scu/volinidebadiwinu.pdfIn PDF document text
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/ksp7f0r1dcajkg188ku3gdm480/49922178399.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608a0cd4a9adc---27913857813.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/40e560c511238efb762cad4a3dd0002c/tuxokijijekizokumibava.pdfIn PDF document text
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/142ce2d1b9d4d1313fd8b724beb8a68a/2451407080.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_off000103f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103F4 16808 bytes
SHA-256: fc8eac21573c0234a8cd8cae20f440449a641cb345ed6ff87d782ebd0319451e
font_01_sfnt_off00012f8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F8C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000147a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x147A3 11028 bytes
SHA-256: 88ebb8936b762ca1bf377eceaf24172553a80ffc5a5d6c834ef99b718d7c7645