Malicious PDF — malware analysis report

Static analysis result for SHA-256 329a422f66ac31a3…

MALICIOUS

PDF

85.7 KB Created: 2021-07-06 10:18:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 224f8c644adb890295dc91b8f9717e0c SHA-1: 5a86fdf5d456f266d4a35704dc8d6b8e09847a2c SHA-256: 329a422f66ac31a36575abf38efc64a9024128b181b7836a11ddb479e3c00ebd
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and disposable domains. These links likely serve as lures for phishing attacks or to distribute further malware payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://inwebjor.ru/uplcv?utm_term=html+to+pdf+c%23+free+library PDF link annotation
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/tj0h5kfd7l69iqfo5i3np1rvk7/judip.pdfIn PDF document text
    • http://duoctruongxuan.vn/userfiles/image/file/vobulak.pdfIn PDF document text
    • http://sgyscom.com/upload_fck/file/2021-6-18/20210618052253574042.pdfIn PDF document text
    • https://www.couleurs-et-jardin.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609e58a72fcdf---92945714082.pdfIn PDF document text
    • https://zlato-eu.cz/upload/files/wiburezotigeribakogogif.pdfIn PDF document text
    • http://renovator.cz/files/file/mikurub.pdfIn PDF document text
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/48nqrqc8dk7a60ub75e29v05i0/38297271144.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/1607f71aa6437b---33067709122.pdfIn PDF document text
    • https://tlpnw.com/wp-content/plugins/super-forms/uploads/php/files/8bf33ab1137e46518b9a6a65afc95a5e/6292254607.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608172a3eaaa3---9826720677.pdfIn PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ef1a9eedd5---vilipozipimijamewazosa.pdfIn PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607159dd48e24---60990071567.pdfIn PDF document text
    • https://pointsourcegroup.com/wp-content/plugins/super-forms/uploads/php/files/ac4029c19330a8a54e77cc997bcb7823/44356357427.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/bbbeff90fc02ab6910267ba24b76d3e7/fedepo.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/f08a8f816fa082f0c1db783b47ab59a4/bipixu.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cff7559c24d---pavosejevibowaragu.pdfIn PDF document text
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/415d969d442f12c541c706d7a9ae8056/55617672698.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a79f8ff1e66---zokarelebud.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/32957835240.pdfIn PDF document text
    • http://theleadershipworks.com/PO2/UPFILE/userfiles/files/vozigego.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/25ca2a7be8f3e5b17adc7fe2782ba51f/84519979961.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16092beb53af34---sakubekimibujegin.pdfIn PDF document text
    • http://3gr-group.com/ci/userfiles/files/kobopubekujafifuf.pdfIn PDF document text
    • http://ues-rb.ru/themes/ues-rb.ru/files/povoteninid.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_off0000ef15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF15 17068 bytes
SHA-256: b472cb44227098b225d5dcfe43b938e02f379fe5d67dd0cde7788fc19285bb40
font_01_sfnt_off00011bbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BBF 10012 bytes
SHA-256: a67be29401885aeb9cebf23bf2b86d7cc02b9d528a6fa7ea26bebb718e0b10c5
font_02_sfnt_off000131ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131EF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1