Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bd78068d72d3c62…

MALICIOUS

PDF

75.0 KB Created: 2021-03-29 08:48:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 6c479b014971bbde6401360b7bddeb5c SHA-1: 0273bc1ef9e4447052447eba3e9a0540c38dffb5 SHA-256: 4bd78068d72d3c620a69f61be44ead3fa1d2b5b5c335aa3a5b8e70762ba2fa88
186 Risk Score

Malware Insights

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

The PDF contains numerous external links, many hosted on disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and embedded URLs point towards a common tactic of using documents to drive traffic to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://mezovuduw.ru/strik?utm_term=turning+challenges+into+opportunities+persuasive+essay PDF link annotation
    • https://cdn.sqhk.co/nogorodizet/fwiiVsY/xokabagura.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4392861/normal_602d211b856ce.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380230/normal_600c83b2ad42d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449996/normal_6061048605721.pdfIn PDF document text
    • https://cdn.sqhk.co/vavetiset/qSdieji/37604996643.pdfIn PDF document text
    • http://zefedupawomodos.22web.org/dasulawisuzobosunobatoge.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481990/normal_5fd11658e7087.pdfIn PDF document text
    • http://mademupo.22web.org/95130733618.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402250/normal_5fe72d24d6a63.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4462775/normal_605b12faa7bd4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4379219/normal_5ff3f9957945e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420761/normal_6046a0b120bef.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393785/normal_604e5b0bec72e.pdfIn PDF document text
    • http://nalowisep.22web.org/39984966770.pdfIn PDF document text
    • https://cdn.sqhk.co/dadirowuj/cI6gcji/xafotipiwuwu.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/a591b46c-646d-43b0-98e6-5fc2ea6ed1e5/36034965764.pdfIn PDF document text
    • https://e5eb5b25-b33c-43e3-82d5-57ab1bf863d8.filesusr.com/ugd/b0c717_c6a6837477964837a9373f0731989915.pdf?index=trueIn PDF document text
    • http://jurixosemur.epizy.com/balance_sheet_analysis_of_banks.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b22272e0-ec35-4b31-8108-18d82f1bb722/is_it_common_for_couples_to_argue.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6a6ee56f-43f6-4d06-ae3b-2bea75113edf/local_area_network_lan_speed_testing_software.pdfIn PDF document text
    • https://1b8131b1-2748-4b03-899c-43b53273a41f.filesusr.com/ugd/e3c460_2880cfc6c6da47158a3043ab31202741.pdf?index=trueIn PDF document text
    • https://b6c9d0de-81a1-4db9-ab7d-8a95af9e63d6.filesusr.com/ugd/b28ae2_959a766c239d4dd68deed1ef19242b1d.pdf?index=trueIn PDF document text
    • https://1b3fde16-7575-45ba-b40e-8916c64185ca.filesusr.com/ugd/8874e8_c69632e49e8a4117b9ec244e74841920.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_off0000e8d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8D3 5308 bytes
SHA-256: bd9cdf9f263d55a5ec65531d30a1b3b18c8f1808a7c7450ab38a1538fa537e8e
font_01_sfnt_off0000faf0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAF0 10320 bytes
SHA-256: 50a105c2dfea9b8532e1e599d506a32453a3905da21102403612bb93b4566ed3