Malicious PDF — malware analysis report

Static analysis result for SHA-256 b626d422f3d3bde3…

MALICIOUS

PDF

74.8 KB Created: 2021-03-31 19:41:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 5603ebb67333a3fbf70e17340e79d8a3 SHA-1: e760864d5a78342fbe194ee026b2e48bed7c62da SHA-256: b626d422f3d3bde3181ef5a28ece378f24df4c236415935ae8c360905dbae234
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which are hosted on disposable domains, indicating a link farm designed to direct users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The embedded URLs and the nature of the link farm point towards an attempt to redirect users to a compromised or malicious website.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://jacksth.ru/strik?utm_term=verbs+worksheet+2nd+grade+free PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4372681/normal_5fc927dc7c672.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4389606/normal_5fe0cbadbe133.pdfIn PDF document text
    • https://kokozorakozuwel.weebly.com/uploads/1/3/0/7/130775651/wijumuju_megomagiduw_xafopanu_keribapafo.pdfIn PDF document text
    • http://maxobujixeweden.sportsontheweb.net/bijajolelusoleneranutaz.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450734/normal_60356f56683a6.pdfIn PDF document text
    • http://wudebakafepi.mypressonline.com/xivedigajirujotaxuvev.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4490252/normal_5fef587dd81fe.pdfIn PDF document text
    • https://nefadojajekewa.weebly.com/uploads/1/3/0/8/130874163/neluf.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://zaduzos.myartsonline.com/periodic_table_crossword_puzzle_answer_key.pdfIn PDF document text
    • http://nojikigor.myartsonline.com/42894847159.pdfIn PDF document text
    • http://bumejefivoxigo.myartsonline.com/81032208057.pdfIn PDF document text
    • https://s3.amazonaws.com/dowavelaxam/how_to_train_for_football_season_ticket.pdfIn PDF document text
    • https://9462281c-6212-45c1-8f90-c4e3c363a226.filesusr.com/ugd/007d40_8452d64dcfcf4104bdcdc6bbccf22d4a.pdf?index=trueIn PDF document text
    • https://dc010c70-835d-4b56-8cb0-1e1bda7cab64.filesusr.com/ugd/fb576b_ff2e691762cc4855bf6cc7d89a9c76cd.pdf?index=trueIn PDF document text
    • https://56076a71-1b70-41e8-afe1-d547c394b4ee.filesusr.com/ugd/ab0d05_35c28c5f0f314ed8bd2dd7ccd70c3f27.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/jusuberu/curriculum_vitae.pdfIn PDF document text
    • https://s3.amazonaws.com/wewuxuviwar/2282336460.pdfIn PDF document text
    • https://ed59cdd8-0d75-4634-8bb2-7afdb9da103e.filesusr.com/ugd/9cb112_864d5538aaa04bb4bf66f68ae9a94153.pdf?index=trueIn PDF document text
    • https://0cfe495c-9a5f-46a1-a5f3-fb21b6211bac.filesusr.com/ugd/7aabb2_250df42087e549a6a5c1f20e2aee85e7.pdf?index=trueIn PDF document text
    • https://c0771fee-1ba5-4dbf-bba5-a775c3d44c03.filesusr.com/ugd/544e7e_81502e4586f54ea09d1c61b9617a3aa7.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/jowutoneranemuk/7428332270.pdfIn PDF document text
    • https://14da0a27-f261-4d4b-8668-3a369f5c966d.filesusr.com/ugd/46429b_bfde31c4263b44dd8ba55b56bbc3a03c.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/xomepixo/karuppasamy_video_songs_free.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_off0000e6c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6C4 5528 bytes
SHA-256: 5cb1dff7155c8e58c43be84a962529480bfdcd22db22993681305358f73cabe8
font_01_sfnt_off0000f9a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A3 10644 bytes
SHA-256: a414ff05a618cd878bdabacfa74912b87c0f58f0251e54ce2eddf3705c0262e2