Malicious PDF — malware analysis report

Static analysis result for SHA-256 0f144323e91e44fb…

MALICIOUS

PDF

74.7 KB Created: 2021-09-07 13:49:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 411361f28629b4708b5205d069bbc1b3 SHA-1: 610e79673a2e6b2b433df6846087d2f4ebfa4ec4 SHA-256: 0f144323e91e44fb9e916798eb24e77618238bbcf6569120ce1adc706c1b6d5e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to exploit users by directing them to potentially harmful URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/8494262ad912a69d513b9a94c0a7e536/xizekojomujizusen.pdf In PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16099a052c71a8---90175431439.pdfIn PDF document text
    • http://ihdbd.org/upload/files/jirageboxogudilar.pdfIn PDF document text
    • http://cartonwrappingmachine.com/userfiles/file/20730515206.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/n80lund19cjb6s9gq9jggd1is2/denowa.pdfIn PDF document text
    • http://aescantabria.es/upload/fckeditor/file///32411057444.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161043f39ac03f---36925030871.pdfIn PDF document text
    • http://superfishinglewood.com/uploads/files/15829042608.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/16077d9001d602---5779048727.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160853fbf49df1---94226600793.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/cfdfa12dd3ef2d59e9d998b9e99c4019/99353795033.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160cfe141df9ce---12195128422.pdfIn PDF document text
    • https://ayurvedaemart.com/uploads/file/33611823177.pdfIn PDF document text
    • https://weeb.nu/userfiles/file/75776370636.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160761b0bc859d---kalawomofipavanojilovi.pdfIn PDF document text
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/ccf7dffd5b8c92fada94128707a9ac8d/85943496307.pdfIn PDF document text
    • http://stitesattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/faboxoxu.pdfIn PDF document text
    • http://bigband-ulm.de/userfiles/files/97771498685.pdfIn PDF document text
    • http://mcap.cz/images/uploadedimages/file/zalizegajaxarogaxefimem.pdfIn PDF document text
    • http://mamtomchabahai.com/uploads/files/files/damewonisozuwewivopimolo.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a3e3545b1a3---16679476138.pdfIn PDF document text
    • http://hopkins1983.com/clients/861771/File/jatorezadawop.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/26636129058.pdfIn PDF document text
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/al6ilam1as8jbo2fi7nhgpgun7/laloduwilikat.pdfIn PDF document text
    • http://duythuc-bearing.vn/uploads/userfiles/file/wanegusavefusaxuxavafavo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=sign+pdf+online+appPDF 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_off0000c3d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3D3 10380 bytes
SHA-256: ffed516271614be706107f0bd5ac962d63198558b3f00fed271d9e479aed5805
font_01_sfnt_off0000db2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB2E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f340.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF340 16296 bytes
SHA-256: f750403b5dc9665aa39843f2f7a36540f97cb9d7e1c85e960d7aa160700bf8da