Malicious PDF — malware analysis report

Static analysis result for SHA-256 62d8d610f2e61843…

MALICIOUS

PDF

71.1 KB Created: 2021-06-25 17:09:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 917e26430944ca4c8f0a454408e6e423 SHA-1: 98133099d0fff16716f0adf64b311d03e37bfd00 SHA-256: 62d8d610f2e618433e6351931bf8a6fbd54a9421db0617ed36992bc39cd7cd65
156 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or redirecting users to malicious content. The document body is unreadable, but the heuristic firings clearly point to a link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://pacie.vn/web/uploads/files/19699266745.pdf In PDF document text
    • http://drukarnia-skawina.pl/app/webroot/media/files/nipubumuganefu.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086e9ca13b37---73279160665.pdfIn PDF document text
    • http://angelescare.com/userfiles/file/39473362206.pdfIn PDF document text
    • http://sotel-perm.ru/site/file/julujosotule.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/35960c5102f1727d8c011607d7a004ff/tefawulor.pdfIn PDF document text
    • http://bigpictureresources.com/userfilesbigpicture/file/sutubefuludetejike.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/cbdce4cae9e97c7aa1a80762635946ae/48529974106.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c29ef2ec25d---73048048770.pdfIn PDF document text
    • http://ebsenglish.net/_UploadFile/Images/file/16815828869.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/160714bd0e3fb1---dubapew.pdfIn PDF document text
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/267e8e1f716e61d719762a958a677569/98186750469.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/caff8b8dca93bd3dd0696ff2a605d5be/rixivuzej.pdfIn PDF document text
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/9889eed7a34fa96b760084c891aec0c0/25527275913.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16079aa14d7775---6306336513.pdfIn PDF document text
    • https://www.ltgpartners.com/wp-content/plugins/super-forms/uploads/php/files/5688c2e1430233f7f0b90438c924391f/20455448412.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=fishing+in+plainfield+ilPDF 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_off0000b648.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB648 10436 bytes
SHA-256: 02f491c86240cb5f8c663f6ede19dd55b2730acb49376a21520572b7927487be
font_01_sfnt_off0000cd90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD90 16392 bytes
SHA-256: 8fbdd8591ea29092f0ebc52cbf7b201cdc012c12a3b2a1fe590c4750ab965516
font_02_sfnt_off0000f7c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7C1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1