Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae049d1ab423c76f…

MALICIOUS

PDF

76.8 KB Created: 2021-03-14 09:51:19 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-17
MD5: 1eb5b244cd3b9796702baad9ae126dfb SHA-1: 88e1f1eb895bd6882f95a0ec09e4a07e1180ea4a SHA-256: ae049d1ab423c76fdbc8f7c54a22318287a7b10371fae9dad71a2750001e114a
126 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO spam operation. The primary URL includes a 'utm_term' parameter that mimics a search query, indicating an attempt to deceive users into clicking through. The ML classifier strongly flagged this PDF as malicious, supporting the conclusion that it is part of a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://leonvi.ru/strik?utm_term=how+does+edta+bind+to+calcium PDF link annotation
    • https://nixuxani.weebly.com/uploads/1/3/4/4/134433038/2465399.pdfIn PDF document text
    • https://rolurenogilu.weebly.com/uploads/1/3/4/0/134096536/6997127.pdfIn PDF document text
    • https://nogonosexenepe.weebly.com/uploads/1/3/4/6/134674491/438774.pdfIn PDF document text
    • https://cdn.sqhk.co/vulovosovem/0gioggh/viridian_green_acrylic_paint.pdfIn PDF document text
    • https://cdn.sqhk.co/vadetegubufo/YKdVCig/warifokijokigudodegetexa.pdfIn PDF document text
    • http://obuv-kozha.ru/palofozelidalugetakaxysqeb.pdfIn PDF document text
    • http://shtangelkipokupkiitd.online/kudejifutoseje2e8m.pdfIn PDF document text
    • https://cdn.sqhk.co/velomegu/hiVjbgx/brimstone_definition_chemistry.pdfIn PDF document text
    • https://cdn.sqhk.co/zuxosutuku/iwx9Njh/jovuruju.pdfIn PDF document text
    • https://cdn.sqhk.co/suzironanes/vhchjQu/94488917632.pdfIn PDF document text
    • https://cdn.sqhk.co/wajerewuwer/nid8cib/8777214159.pdfIn PDF document text
    • http://znasila.ru/thrustmaster_t-flight_hotas_x_flight_stick_xbox_one609kh.pdfIn PDF document text
    • https://xorimaki.weebly.com/uploads/1/3/0/7/130739578/fezaf.pdfIn PDF document text
    • http://straponartist.com/zewabu6msiv.pdfIn PDF document text
    • https://cdn.sqhk.co/luketopaja/Aijiiic/gedovo.pdfIn PDF document text
    • https://mabaxezo.weebly.com/uploads/1/3/4/7/134766945/bukajumolumuwiw.pdfIn PDF document text
    • https://cdn.sqhk.co/vinikawikuve/ShfahfS/mathletics_student_app_for_iphone.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/5babc44b-0bee-466e-8b5d-47b69ce34332/49338512079.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c440b1ee-a422-4a21-a530-d0564d81670f/65046125953.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cd7f5c5a-80c8-4084-b84b-b59ee16dd846/62698363253.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a9595772-c3ad-4236-953d-a0a34bc1e60f/1993_apush_dbq_answers.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_off0000efa1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFA1 5184 bytes
SHA-256: e65782f08793236b2cc50b1252841931183ada469c69052c09d2a6fe35e09331
font_01_sfnt_off0001013b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1013B 10896 bytes
SHA-256: 241473504f42a07e7021395540f692997cfda6f4a7fea5767f82b2735ca65a4e