Malicious PDF — malware analysis report

Static analysis result for SHA-256 731ef0791978dc5a…

MALICIOUS

PDF

76.6 KB Created: 2021-09-22 22:57:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 9128edc27ec42e0371645078ebdf1a65 SHA-1: 444e77400df0af205be8f43157dbd7671a05d212 SHA-256: 731ef0791978dc5a68c16122b3b4f2ec80e6915ef80b70505a21e925b9e689c0
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The presence of numerous links, including one with a 'utm_term' parameter suggesting a lure for specific content, points towards an attempt to redirect users to potentially malicious sites for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://tsegypt.com/file/ribafavebew.pdf In PDF document text
    • http://hosteleriayvending.com/ckfinder/userfiles/files/16188385501.pdfIn PDF document text
    • http://udokutscher.de/gfx/userfiles/files/20851445424.pdfIn PDF document text
    • http://lokalizacja-gps.pl/userfiles/file/geditixabebizej.pdfIn PDF document text
    • http://daiichibus.vn/uploads/news_file/gufirugujotunefakezefi.pdfIn PDF document text
    • http://arkystudio.eu/userfiles/files/wawajizimokajijedo.pdfIn PDF document text
    • https://shoppingplanet.cityplanet.ro/ckfinder/userfiles/files/48481264832.pdfIn PDF document text
    • http://studiozoppini.com/userfiles/files/neramubujawawo.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/chgbr7h18fanoasbf4j5t85rvc/zelivuwawowexup.pdfIn PDF document text
    • http://rkmaster.ru/uploads/files/tenavojapaduniwebonopimag.pdfIn PDF document text
    • https://biocoils.com/img/file/gidepirixukekusipe.pdfIn PDF document text
    • http://goopenapp.com/uploads/files/zatozaxadepokilidajixex.pdfIn PDF document text
    • https://szamitogep-szerviz-javitas.hu/ckfinder/userfiles/files/wajibakugobimexinajebozid.pdfIn PDF document text
    • http://fthyhs.com/resource/docContentImg/file/2021-09-07/08fa60d104b818873dd9d92223bafb87.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/0bc2f3fe5413d5c63892c7ad1a8158d5/19543854956.pdfIn PDF document text
    • https://100tmt.com/uploadimage/files/20210905103338.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136a43653609---82037665029.pdfIn PDF document text
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/161339d57093a8---nivobojedulorulig.pdfIn PDF document text
    • http://indecomavo.pl/userimg/inc/59441503488.pdfIn PDF document text
    • http://homespakistan.net/magzine/uploadfiles/file/91643517931.pdfIn PDF document text
    • https://unitedpetexpress.unitedreloth.com/ckfinder/userfiles/files/dunofogerizobesoxinas.pdfIn PDF document text
    • https://eownauto.com/uploadpic/files/31220220712.pdfIn PDF document text
    • https://chokysitohang.com/Uploads/userfiles/files/tatidam.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=thor+ragnarok+full+movie+download+in+tamil+hd+1080pPDF 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_off0000c181.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC181 11468 bytes
SHA-256: 424d4737f59bf533c162bc1ab53b2ad912e141448ab68286e7149e2182fc083f
font_01_sfnt_off0000dc53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC53 18388 bytes
SHA-256: 9c1957b03e18d26d91fc92466d6e80dd3034a34e28b0c28991836b2315aa983d
font_02_sfnt_off00010cb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CB9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1