Malicious PDF — malware analysis report

Static analysis result for SHA-256 159b81e1f75f2f92…

MALICIOUS

PDF

88.0 KB Created: 2021-05-28 08:03:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 0b3d9645d1dd47374a542119386c3612 SHA-1: f3c4af8ef7fb3fd2dcbe787c2d6921b661e7cd13 SHA-256: 159b81e1f75f2f928401d34efc928670981a93cf9d7ada7235fa39ac7db81b8b
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

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. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9967

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://jumiwimov.ru/strik?utm_term=how+to+self+clean+rowenta+iron PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4374380/normal_604aa1d5b4cee.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4491169/normal_5fdd3143525a8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459941/normal_6014d5052eaa8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4500201/normal_6020bf08e20a6.pdfIn PDF document text
    • https://rozinefowo.weebly.com/uploads/1/3/4/5/134576391/ruritu_nasowarax_xoxusile.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4456369/normal_605be4fee4a1e.pdfIn PDF document text
    • https://lemusudavigi.weebly.com/uploads/1/3/5/3/135395292/pebiliwetufunalejag.pdfIn PDF document text
    • https://xexifenenufomag.weebly.com/uploads/1/3/6/0/136082553/2788828.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4403806/normal_5fc5d80b14361.pdfIn PDF document text
    • https://ximofutaxa.weebly.com/uploads/1/3/4/6/134626718/9202647.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413455/normal_5fd81aeb9baf9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4456686/normal_6025b2f04fd07.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371808/normal_601616e2dc3bf.pdfIn PDF document text
    • https://fopidezajot.weebly.com/uploads/1/3/4/6/134688075/1700330.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/7eeeb6d7-f923-4d92-b1c6-4260f8300c6b/jozejadexevi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b577f49c-bc8f-4b7b-8317-40b2e80628ae/gesatetibopevalofab.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8d08ef11-5b71-4b97-b44c-8575baa12d0f/weber_charcoal_grill_lid_gasket.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5d0f2f86-9dbd-42d2-ad56-2d21807c4252/thank_you_gift_mother_of_the_groom.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eed3633f-a834-4889-928b-fb383eb94ce6/99746070917.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/020a44dc-da6e-4d8e-a786-9ed50cf6c136/84563324066.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/338e3359-d58b-4248-a73b-c32301ea6e50/wolf_oven_cleaning_guide.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dbd79c8f-46cf-4cb1-acbf-ca3dcac60dc6/ditch_witch_jt20_parts_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ab47467f-7ccc-434f-a89e-a71edc829ef2/biforutoposizajufavikip.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/06086c5e-1a69-4748-ad34-abe7fbe8df58/89013033957.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fffa5346-76c7-4ac4-b978-f0a86cd1a6ed/how_to_use_a_non_contact_thermometer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/30fbaf15-8a83-4135-bff9-e402120860a4/82678554925.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9ab4635f-827d-4b32-bb01-0d1e703ed587/what_is_the_purpose_of_a_reflection_model.pdfIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001191a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1191A 4928 bytes
SHA-256: d0594d931196f534f2aff69b6c1d65be349298377cb7923f4a5b712dc6950b42
font_01_sfnt_off000129fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129FD 11340 bytes
SHA-256: 0b60448d5edeaf2f0ed35c0d68bfd6184dab6102208a79da18981a12beb0b653