Malicious PDF — malware analysis report

Static analysis result for SHA-256 3518f8c67755979a…

MALICIOUS

PDF

79.5 KB Created: 2021-05-11 07:04:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 3d322bf4821b2da51db2f3db1dcbd5da SHA-1: 251db4528c78b1f77c069ac7a23c8b8cac2803c0 SHA-256: 3518f8c67755979a0b0b0541d65626890f00a28f4f76ea7cc39f5c7938c65e55
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 hosted on disposable domains, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a phishing or malware distribution campaign, likely initiated via spearphishing.

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://jumiwimov.ru/strik?utm_term=how+to+program+a+valet+key PDF link annotation
    • http://just-gopro.com/57109046096m0r2p.pdfIn PDF document text
    • https://cdn.sqhk.co/bewewojiwo/cCTYMib/zombie_sniper_shooter_3d_apk.pdfIn PDF document text
    • http://dezlice.ru/kelobuvigeyl0fm.pdfIn PDF document text
    • https://cdn.sqhk.co/sipebesoxu/CbT1ghp/everfi_module_5_credit_scores_answers.pdfIn PDF document text
    • http://nepoxiduvilej.scienceontheweb.net/pinufivujizizu.pdfIn PDF document text
    • http://balifruit.com/sizunaminalikokewivefazehpq6n.pdfIn PDF document text
    • https://cdn.sqhk.co/vefuwatak/cUungdl/sudubil.pdfIn PDF document text
    • https://cdn.sqhk.co/nebemina/djaDqig/nobakifu.pdfIn PDF document text
    • http://zipubezexupoka.mywebcommunity.org/nuclear_waste_management.pdfIn PDF document text
    • https://cdn.sqhk.co/kidurukazag/wUjgjfl/texas_smash_my_hero_academia.pdfIn PDF document text
    • http://ig-support-service.com/8133747153r2doj.pdfIn PDF document text
    • https://cdn.sqhk.co/zobelekivix/bEiggjN/small_woodworking_projects_book.pdfIn PDF document text
    • http://helpverifybadges.com/470434757917ayhw.pdfIn PDF document text
    • https://cdn.sqhk.co/rupomotiz/hbXhccH/callaway_golf_clubs_set_for_sale.pdfIn PDF document text
    • https://cdn.sqhk.co/lumozupa/vihibih/accessions_medical_history_report.pdfIn PDF document text
    • https://cdn.sqhk.co/tibakekavero/1jdhhVr/poginubobovavibepagif.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://104e3d6a-8609-4a5f-ba89-88df40aeb326.filesusr.com/ugd/3cb22f_ddea096decb14ea489a66aeb3ac4258a.pdf?index=trueIn PDF document text
    • https://49550882-97ce-44db-a38b-6e383bb81149.filesusr.com/ugd/062c90_2491e188e16b4698a54196f7597379f0.pdf?index=trueIn PDF document text
    • https://7fca5364-97a1-4441-b76e-d2c429a59218.filesusr.com/ugd/735424_c4d95f5418764e298bd641d384186751.pdf?index=trueIn PDF document text
    • https://78a3f932-2eca-4366-91b9-d52a2f3c5f58.filesusr.com/ugd/a586f9_bc0c7360c9514208ba504e9383af461a.pdf?index=trueIn PDF document text
    • https://98350ace-7ac4-4f38-a9d9-579fdad8050b.filesusr.com/ugd/9b2d9b_662fc1743b1e43d48a8fb87a13d05e17.pdf?index=trueIn PDF document text
    • https://8d59741e-369e-44be-b01e-8fbcb09d2d01.filesusr.com/ugd/7cefa9_113e43b4b3ca4d8b9c5d242624cdf916.pdf?index=trueIn PDF document text
    • https://492f55f4-3442-4b37-b17e-39d9f2f0ae8a.filesusr.com/ugd/7dfe85_c7e3a6d5145e45d9810ede3de6dc7e68.pdf?index=trueIn PDF document text
    • https://57933e30-1e86-4cbe-ad2b-777cb72f9932.filesusr.com/ugd/235f1a_2c04e41fdf8e495386856756c3b144af.pdf?index=trueIn 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_off0000f8cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8CC 5240 bytes
SHA-256: a757bbe653458a4bb8c57fb3b247d12b7f919aaffd3f86deed3e2326585d9826
font_01_sfnt_off00010aa9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AA9 11180 bytes
SHA-256: 9580eb85f27c89cccbba0ec6abd6040cbf9dae03eb2791fd6a6ff24eb92dacac