Malicious PDF — malware analysis report

Static analysis result for SHA-256 52b8ef834a357c13…

MALICIOUS

PDF

89.2 KB Created: 2021-05-10 06:28:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: dad728ec740c000b47870d95b2c536ce SHA-1: e635abc38721475440ae7a56acd77e655eec7931 SHA-256: 52b8ef834a357c13f6c9aed710106c873ae615de9f9450f69362b87ba4f03259
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links pointing to compromised websites and disposable hosting, indicative of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are sufficient to infer a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/bbb4iu3nb1sil4ot2lnlt5p5km/26159875699.pdf In PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609440edda500---19252615233.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/2b5a515a1b426e1981b36ae3f10bf4d5/89868363281.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075a73f7c45a---18341123423.pdfIn PDF document text
    • https://myveolife.com/wp-content/plugins/super-forms/uploads/php/files/35e28b334184aff2f3decf9689c23543/10062854689.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/b864c09448d892665197a61d5cef0f67/wozejoja.pdfIn PDF document text
    • https://www.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/22fc07798389ab35dbcdf0ab48d73849/1174598645.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/f3ce38b20a26917c62109287375a398a/96872045739.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/trrjbvhqmmbbh2kqkrjlv92q5g/bufarudatitetov.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608f789ac4495---22239615947.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607f2c915033f---veteretofafota.pdfIn PDF document text
    • https://bellevuecommunityfoodbank.org/wp-content/plugins/super-forms/uploads/php/files/5fa8ee09d7bb9a7f155abb2ab22f1380/5829054376.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16075aeb098580---rojoj.pdfIn PDF document text
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160909f48d8af4---somuvewevuluxabeparo.pdfIn PDF document text
    • https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/55d28a79724382bde99a13618b73e756/wudedefabediduniwa.pdfIn PDF document text
    • https://majorsagilekvaros.hu/uploads/file/8869941165.pdfIn PDF document text
    • https://floridaholidayplanner.com/wp-content/plugins/super-forms/uploads/php/files/2995f7301eeb290a4a575dfb7b7315bb/95205392959.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/160905493264b1---tufonuligaxezobapigero.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=black+and+decker+gl300+manualPDF 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
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off0001392e.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x1392E 18728 bytes
SHA-256: 2ff921d1f9098d78c40319f5d8d207ec49872231fad6082df5657ec83ec7220f
font_00_sfnt_off0000ff83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF83 5500 bytes
SHA-256: 8a43f6e7f2d3f52a4818c7a1e65bb90e2f26431b1a8836a1b724144da7117b56
font_01_sfnt_off00011226.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11226 11472 bytes
SHA-256: 96c74e27ff8d5a861f7a51612090b897cd18961c79df04f0b21c5897bbdf4ee6