Malicious PDF — malware analysis report

Static analysis result for SHA-256 8188607126391623…

MALICIOUS

PDF

77.0 KB Created: 2021-06-01 11:52:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: dc53eab8c6229e5f92d2facfba70c512 SHA-1: 04b22a74a30358d2541c2438bd021b509cd5db4f SHA-256: 8188607126391623834171ab4e34074cb5aa849b215f8e946be705210db9eb9b
186 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, which is characteristic of SEO link farms or phishing lures. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. The embedded URLs are the primary indicators of compromise, suggesting the document's purpose is to redirect users to potentially harmful content.

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://botokaw.ru/123?utm_term=libros+de+centrales+termicas+pdf PDF link annotation
    • https://mululugasafes.weebly.com/uploads/1/3/1/6/131636627/3029849.pdfIn PDF document text
    • https://pemiroma.weebly.com/uploads/1/3/1/3/131383733/6816546.pdfIn PDF document text
    • https://gatilavim.weebly.com/uploads/1/3/4/3/134391542/wepebefemoma-kogogogofaw-lopatal.pdfIn PDF document text
    • https://tekuxarutupun.weebly.com/uploads/1/3/0/7/130775258/1795435.pdfIn PDF document text
    • https://rutisipileriruk.weebly.com/uploads/1/3/2/7/132740940/pajexakawik_verunokironol.pdfIn PDF document text
    • https://rajukoxo.weebly.com/uploads/1/3/4/5/134508115/ebbdcb72447.pdfIn PDF document text
    • https://tidivexosito.weebly.com/uploads/1/3/4/3/134316292/d93c53d3612.pdfIn PDF document text
    • https://sutowuvo.weebly.com/uploads/1/3/4/6/134685384/nufukaguje.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4451544/normal_5fe5ad09800c1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476273/normal_60601e4578555.pdfIn PDF document text
    • https://tekuxarutupun.weebly.com/uploads/1/3/0/7/130775258/ruvuvogivi.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4393925/normal_5ff7f8d24ff96.pdfIn PDF document text
    • https://kamejufozafa.weebly.com/uploads/1/3/4/8/134891268/dadunorupelirob.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486199/normal_6025c08f34962.pdfIn PDF document text
    • https://tusefekojeseto.weebly.com/uploads/1/3/4/4/134437698/furegugazezimonid.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4452381/normal_5fcad2efa24f3.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/d2157894-872a-4dc1-ad67-8daef86586b9/best_inexpensive_riding_lawn_mower_2019.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/08cfceb1-425b-40af-b884-a2204f3879c3/how_to_use_an_ipod_shuffle.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0551a972-0e63-4ea5-b720-65d19a368322/what_size_battery_does_a_genie_garage_door_opener_take.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6b6c8721-0200-409a-8648-2c8799e227be/nancy_drew_tv_series_characters.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b3e41831-8269-41d6-aaeb-f9d3e88be38d/70442206802.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_off0000eb28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB28 5384 bytes
SHA-256: a5d773c9c74ae97d38ce7922a8440a52bcd76b1e7cd3d98279323f70a05c26a8
font_01_sfnt_off0000fd5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD5B 12100 bytes
SHA-256: ea21c20f363fc803923cb66a0d1ce13df1872b60169a587afd8c2c201f36d768