Malicious PDF — malware analysis report

Static analysis result for SHA-256 53bdbd588be9a3cd…

MALICIOUS

PDF

75.2 KB Created: 2021-05-19 20:53:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: c4b1ef697704f61bc518123ad585d8f9 SHA-1: 5c03a8a17841aa519690b31ecd9eb4b886724e6d SHA-256: 53bdbd588be9a3cd3ba537a7787c0309597861271e1ef02b8c6f119dc4ed6b5d
186 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, suggesting it functions as a link farm designed to redirect users to potentially harmful websites. The presence of embedded URLs and the heuristic firing for PDF_SEO_LINK_FARM strongly support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://druttle.ru/strik?utm_term=what+is+electrical+work+permit+on+ship PDF link annotation
    • https://pakotoroxup.weebly.com/uploads/1/3/0/8/130815058/kinapefumojuv.pdfIn PDF document text
    • https://bipixexomalexu.weebly.com/uploads/1/3/4/3/134349320/bezugosidu_panigasifeworux.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4495400/normal_6007d1e391ffc.pdfIn PDF document text
    • https://fenejetamop.weebly.com/uploads/1/3/4/6/134697978/lisesujef.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4380382/normal_5fff5fefda8f9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409095/normal_6035c0914bb3f.pdfIn PDF document text
    • https://wosuletoxo.weebly.com/uploads/1/3/0/7/130739711/wixepogepevusen.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444623/normal_60166eeb3281e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411696/normal_605b333d4fc04.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4482230/normal_5fcc9b47bd6e3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455380/normal_601a4b5f34bfe.pdfIn PDF document text
    • https://zutiwijutorezaz.weebly.com/uploads/1/3/4/3/134354078/wetekexan.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4416131/normal_6000340e46209.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/95161527-de26-4b0a-acd0-2880f0e35460/how_to_connect_jabra_freeway_bluetooth_speaker.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8f70bc7a-ae47-42d3-ac16-59fd4e698e53/competency_based_interview_questions_and_answers_customer_service.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4915b528-e64e-4eda-92a2-859feb05b0ef/98929946417.pdfIn PDF document text
    • https://s3.amazonaws.com/befarekogol/55179431449.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6b46c126-3f7e-4d9a-9ec2-c4a94c2c0bb6/zukisefifasove.pdfIn PDF document text
    • https://s3.amazonaws.com/tixedujegibex/fusawagutiwotowanefugus.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/059f2df5-6783-4456-a24e-ab4c9dda7bef/97033368974.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/657e9bf2-b87a-4280-96de-99be130133a9/what_type_of_oil_does_a_toyota_rav4_use.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c0e9fa89-5f78-4cf7-b169-068b60b0864c/tajusugimuza.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_off0000eaad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAAD 5344 bytes
SHA-256: f15c7cb631dbdc50a4220747548c06acc69dea4d1c73ec58b45291638bed09b9
font_01_sfnt_off0000fcc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCC8 10040 bytes
SHA-256: b3bb2049a34688b9fd53e83da197f92261eda23faa42212611e0995f9e1807d3