Malicious PDF — malware analysis report

Static analysis result for SHA-256 c147a756cc04b226…

MALICIOUS

PDF

77.1 KB Created: 2021-05-21 11:03:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 962367bd35977e643f8492e752bf9449 SHA-1: cd3c36552b2b02c4d4888ea9b7b8894d266fd40c SHA-256: c147a756cc04b2267d2fa9af59c46cdb762924ffe85cd02dd48289521c8b6ccc
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The document contains a large number of external links, many hosted on disposable domains, suggesting a link farm or phishing operation. One of the primary URLs, 'https://nipisod.ru/strik?utm_term=how+to+apply+nsfas+bursary+online', appears to be a lure for bursary applications, likely redirecting to a malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://nipisod.ru/strik?utm_term=how+to+apply+nsfas+bursary+online PDF link annotation
    • https://monijakuxit.weebly.com/uploads/1/3/4/3/134362478/7521089.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4426063/normal_5fe5893dbdb3a.pdfIn PDF document text
    • https://pulolated.weebly.com/uploads/1/3/0/7/130740140/4001013.pdfIn PDF document text
    • https://riguniliwegab.weebly.com/uploads/1/3/5/3/135342973/vukipagenokubipu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459466/normal_605ffe5c5d8f8.pdfIn PDF document text
    • https://diwowure.weebly.com/uploads/1/3/4/5/134592565/5884923.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4468536/normal_6056f7528e484.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365607/normal_60376264cd950.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366660/normal_604cdb4117b92.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381105/normal_6052dec65cc37.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420752/normal_604494b06bd38.pdfIn PDF document text
    • https://vogexuweju.weebly.com/uploads/1/3/0/9/130969932/juduz_juzuwaj_foxaruzurat.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466173/normal_606c1a696eecf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414489/normal_6025965ac9a64.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474223/normal_605fa65a43ea5.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/3b3acd51-ce2c-4d8b-bf08-99d61cd18e1d/puxefigepanujuzejavuj.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1d6081c3-1def-4fc2-afab-12b07885318e/fesidotekikumisiviguku.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/526b8fbc-15bc-4f46-8e84-538243efb98e/wivagonati.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f7945edc-54ed-4217-b23f-70116ce0c891/tirunosajojukuredavi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/072b2326-e589-4e4e-83ef-2039e7d539ae/doxufokisefow.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9d8312e0-e64c-42af-a8ff-05e91f32ae8b/amas_2020_winners_taylor_swift.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_off0000f1d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1D5 5188 bytes
SHA-256: 151050661c3ea013c4f0bfb80582768eb55f46b3500aea84ec6e6c50a57af648
font_01_sfnt_off0001039c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1039C 10520 bytes
SHA-256: 96e1ac7cf39d6d9d016c84cb391f60f6e35ac2f785df8366fdf739b3fc7a5115