Malicious PDF — malware analysis report

Static analysis result for SHA-256 d88f7bf8a81d5e21…

MALICIOUS

PDF

76.9 KB Created: 2021-09-30 11:34:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: a2b36290a8b5e96e65cffb872d49e1fa SHA-1: 18340cc9d8a4f3f19caddb5a1b77c769710b0b21 SHA-256: d88f7bf8a81d5e21dc47ac0a4401bff025d75c94b649fd41ff1720025c82e3c5
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of embedded URLs, many of which point to disposable hosting or compromised CMS upload directories. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of link farming on potentially untrustworthy domains. While no scripts were extracted, the structure and URL patterns suggest a malicious intent to redirect users, likely as part of a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • 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://elisa5888.com/shopadmin/upload/files/tagivefudaraze.pdf In PDF document text
    • http://surtek.biz/image/files/20150407_153447.pdfIn PDF document text
    • http://guowangcable.com/d/files/juraxivos.pdfIn PDF document text
    • http://urdu-hadith.com/survey/userfiles/files/88639155638.pdfIn PDF document text
    • http://live-net.it/file/87457909583.pdfIn PDF document text
    • https://otoform.com/upload/ckfinder/files/wavujufagax.pdfIn PDF document text
    • http://shbaicun.com/userfiles/file/2021090719572273499.pdfIn PDF document text
    • http://0985028898.kad.tw/kads/ckfinder/userfiles/files/42366775228.pdfIn PDF document text
    • http://gloria-eurex.com/images/blog/file/bimozenesurop.pdfIn PDF document text
    • http://psn-monolit.ru/img_file/files/89559766810.pdfIn PDF document text
    • http://biomax.shop/filespath/files/20210917180641.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614cb0f27b5e5---gezixepefirumevuw.pdfIn PDF document text
    • http://autoescuelatosal.com/galeria/files/kukekum.pdfIn PDF document text
    • https://croatia-flyfishing.com/files/pobukowegofimogu.pdfIn PDF document text
    • https://manage4.realtourvision.com/rtv/ckfinder/userfiles/images/files/dizojetilozegabutu.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/d47t2ehe5s3bso25mkcv85a6r3/duzexovepiwo.pdfIn PDF document text
    • https://egyediajandekotletek.hu/mvc/userfiles/file/90667073767.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/ce9vft4ndeqhfirj3jr8ffb0ug/77993131157.pdfIn PDF document text
    • http://niezapominajkowo.eu/userfiles/file/10357707016.pdfIn PDF document text
    • http://mwcapital.net/ckfinder/userfiles/files/66421737834.pdfIn PDF document text
    • http://nerezove-kuchyne.cz/UserFiles/File/19603908316.pdfIn PDF document text
    • http://millenium.moscowfashion.net/content/xuploadimages/file/fuzinerunexi.pdfIn PDF document text
    • https://iqrainternationalschool.org/_assets/files/jibatabulewitovuruvo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=mi+tv+stick+bootloopPDF 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_off0000c1ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1ED 10160 bytes
SHA-256: 499c5955290bda9ab368fc24fb06fe2369b5265b90e3124a10704d0c397c4584
font_01_sfnt_off0000d898.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD898 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f0aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0AA 19684 bytes
SHA-256: 4509cbf92661f44fea385c0ad2c31677806489954d0fd5d90761ecffad0e0f73