Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb789cad1913e1a6…

MALICIOUS

PDF

78.0 KB Created: 2021-09-05 23:23:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: f9379e36e983871d6b579cb5143653f8 SHA-1: 6aa2f61567493639113710f34f0c8e74e66c6a1f SHA-256: cb789cad1913e1a69445daec7aebba8eb36192af6b81cb8ea2cf5b54f0b6ba6c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089c449d8d0d---molujas.pdf In PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607becb20bb5a---vitejiwonexukiju.pdfIn PDF document text
    • http://zzquansu.cn/d/files/90244360424.pdfIn PDF document text
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/0e08070b221b8e772a7b03fe692e8b84/87374603357.pdfIn PDF document text
    • http://pamatudarbai.lt/ckfinder/userfiles/files/4408780005.pdfIn PDF document text
    • https://rh4-h1tapi-turbo.com/contents/files/bawumibarajibalelemazavi.pdfIn PDF document text
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/2f0po1qfv7uppe0qemrjblr002/namosakiminafopazozuliko.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f2672b3b89---79247703968.pdfIn PDF document text
    • http://lejuriste.ru/files/file/fesesugijufisepa.pdfIn PDF document text
    • https://zemiigori.com/uploads/file/3512160333.pdfIn PDF document text
    • http://xn--80aamdqpfpr.xn--p1ai/upload_picture/moroweruxema.pdfIn PDF document text
    • https://cambodiadriverservice.com/userfiles/file/movev.pdfIn PDF document text
    • https://thokhoavietnam.com/upload/files/72675663280.pdfIn PDF document text
    • https://goldgreiner.de/userfiles/file/zelenefuxutomu.pdfIn PDF document text
    • https://holyfamilyhospitals.com/ckfinder/userfiles/files/71500371425.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160829d428bebf---gekegineguvozagowana.pdfIn PDF document text
    • https://excellencetogether.com/img/files/file/momeriw.pdfIn PDF document text
    • http://saveursetsavoirs.fr/image/file/65135980038.pdfIn PDF document text
    • https://seeandhearbetter.ie/img/shop//contents/rejezov.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/16112d4608662f---24747298030.pdfIn PDF document text
    • http://soc-in.com/data/media/files/66589774634.pdfIn PDF document text
    • https://rts-wm.com/ckfinder/userfiles/files/17104400363.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=forex+trading+sessions+pdfPDF 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_off0000cdb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDB6 17108 bytes
SHA-256: e1fa690fae2f703e13c1bd9df4dced0d782d59caa092382eb05a011e10c0cadd
font_01_sfnt_off0000fa14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA14 10708 bytes
SHA-256: 8456fd50ab8a56b198ed40d3717d648e2a58671357a67a3fb00ef66bdc4b0aae
font_02_sfnt_off00011293.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11293 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1