Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd94c7ef9eaf82ae…

MALICIOUS

PDF

76.8 KB Created: 2021-04-12 12:10:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 35a87caca2957612fe73190eb11a1edb SHA-1: 8006e3b47c32c813797917ba0e3bf6919d0603ee SHA-256: cd94c7ef9eaf82ae01deb9d7a6eb3601dd7c4e7762c9b73d670588af5089f22d
186 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many hosted on disposable domains, suggesting a link farm or phishing operation. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and numerous embedded URLs point towards a spearphishing attachment used to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://golowaki.ru/strik?utm_term=how+to+adjust+acer+monitor+screen PDF link annotation
    • https://badosajag.weebly.com/uploads/1/3/1/4/131407507/efb5f9d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465685/normal_5fd30a14bb9be.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454054/normal_60362ce8a86e9.pdfIn PDF document text
    • https://negowuvezesat.weebly.com/uploads/1/3/4/8/134859399/xigimu_funoroneb_falitadofamuxox_tusobo.pdfIn PDF document text
    • http://sokobumoxagug.scienceontheweb.net/wibijapasujugunat.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4455399/normal_600392a3672e7.pdfIn PDF document text
    • http://rejemezurufoveg.mywebcommunity.org/what_time_does_the_stock_market_open_my_time.pdfIn PDF document text
    • http://kurixuj.sportsontheweb.net/59388562312.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4416506/normal_6003d3666a49e.pdfIn PDF document text
    • https://balusapox.weebly.com/uploads/1/3/1/3/131380564/sifupofatewif_jomuvofaw_pajiwu_xajuxilit.pdfIn PDF document text
    • https://fikejibin.weebly.com/uploads/1/3/4/3/134331262/0deac515c28.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413120/normal_60643c952ad20.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/memexelu/dolagibunudajezawu.pdfIn PDF document text
    • http://wenibeliso.atwebpages.com/86350022442.pdfIn PDF document text
    • https://56a7be67-7dca-40da-a973-69ad719fb73b.filesusr.com/ugd/fedf23_4e1af2b077f74a34b81464cf1d7c6467.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/d515f996-0dcd-4512-bb09-5c69ef6d8822/jlab_bluetooth_headphones_not_connecting.pdfIn PDF document text
    • https://ef2e072a-e8a2-4438-804d-cc750be2e2f6.filesusr.com/ugd/6a22cb_e5fd2626757d495ab4cd8b5ed750b0d4.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/zaxawetawupo/7104518443.pdfIn PDF document text
    • https://7ef7ebf0-bcb0-4ca2-8538-5a19c3e9f01c.filesusr.com/ugd/aff7ca_8aab3b09f6eb41e4b1bbdf29d37199bc.pdf?index=trueIn PDF document text
    • https://8eeb1f0a-0cdd-4c66-98a4-83777b49fb54.filesusr.com/ugd/64f9d2_8ceac636c7ef4654a44288f7a8768039.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/293dcf87-46d5-4aa0-b7b9-71a32ad9e42c/pajelidureriromu.pdfIn PDF document text
    • https://9334512a-4df1-45dc-8804-f0fa1d9e2a3d.filesusr.com/ugd/9466eb_72051782e23c4124b4b7f707a4b04a6c.pdf?index=trueIn PDF document text
    • http://fegoluvarelewum.myartsonline.com/muwinuniteriruru.pdfIn PDF document text
    • https://s3.amazonaws.com/divexikav/17267705430.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_off0000ef11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF11 5184 bytes
SHA-256: 2722ffa2384420bfc62270898ad898cf8e44bd6e7810474125a2c9cb03f2fc27
font_01_sfnt_off000100b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100B0 10884 bytes
SHA-256: d80a6d1be101a9ce264761e97449f6a5d097d4ff5ec12222ecb39eaab6671b2f