Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c4be31ec6f0e878…

MALICIOUS

PDF

75.8 KB Created: 2021-03-09 21:48:10 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-20
MD5: 070ff205ace37c618518c25c0c1a3dff SHA-1: 40d20f6b46acf6f683881d7f33a88df28313270f SHA-256: 3c4be31ec6f0e878f59a03364d8adffe92c26052ca00dc2bb118259af215c127
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of external links, many pointing to disposable domains and Weebly hosting, indicating a link farm or SEO manipulation tactic. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the sheer volume of suspicious external links suggests a high likelihood of malicious intent, possibly to distribute further malware or engage in phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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://gimoguvi.ru/123?utm_term=template+ppt+free++2019 PDF link annotation
    • https://tamipabofoj.weebly.com/uploads/1/3/4/8/134876193/a729d83cfe7da.pdfIn PDF document text
    • https://tekejixebosij.weebly.com/uploads/1/3/1/4/131452745/6427487.pdfIn PDF document text
    • https://rabuwamefikulo.weebly.com/uploads/1/3/1/3/131398373/kupilizabonezik.pdfIn PDF document text
    • https://kavirozix.weebly.com/uploads/1/3/3/9/133999962/vabivuz-debasejusis.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4416332/normal_5fff3207150dc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4468530/normal_601a388f8158b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460066/normal_6044cf400dab7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486193/normal_6030cb8a067b7.pdfIn PDF document text
    • http://kewujedirolut.22web.org/futovasazib.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/d1588425-7519-4312-b5b9-d00b26abf74e/56133529094.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7a61fe80-cc7d-4bbb-b4dc-d4797de9bfb4/what_to_do_if_sentry_safe_wont_open.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6770d8a3-0711-4919-92ba-49939c152d17/6543935278.pdfIn PDF document text
    • https://s3.amazonaws.com/gumegulaxi/95790014213.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7577139e-b1ce-4f6a-ac85-8391384e647c/sozaxipuj.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c1faf602-635c-49c1-b083-8ec480df05fe/how_to_explain_poetry.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1a9b244e-1ea6-48c0-9814-e1f9d486bfcc/77915115459.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2501e91a-d10e-4c47-9b06-3eb9e5575137/the_real_book_6th_edition_c.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4e71df03-44b3-49f1-a1c5-a14f3f80fab5/tikeg.pdfIn PDF document text
    • http://dokagokopadodo.rf.gd/bangla_boi_online.pdfIn PDF document text
    • https://s3.amazonaws.com/zedudo/mental_maths_questions_and_answers_year_6.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9cc60181-00af-4af5-8881-e7f32a9c3a60/88216856703.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_off0000ebf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBF9 5300 bytes
SHA-256: 6e6922895aff6173423795d4117e13beb84cef6a16ea3f2a9e6b25fb6ad2b85f
font_01_sfnt_off0000fdef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDEF 10636 bytes
SHA-256: dacd289cda739db4f1caa70249fd191096cfe0c84e944cdd2e892b68bdff87c9