Malicious PDF — malware analysis report

Static analysis result for SHA-256 3972691bf537a7b0…

MALICIOUS

PDF

69.6 KB Created: 2021-09-15 17:22:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: d2f8c4b5514a661259944e02a671c348 SHA-1: 93c67fe11f6b38bf691d20ec4378195f20977920 SHA-256: 3972691bf537a7b0e910870656d617c050b272a9e59023554da1aa50682f1330
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress uploads and disposable hosting, suggesting it's designed to redirect users to potentially harmful sites. The presence of multiple unknown URLs further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://tns-china.cn/editor_upload_image/file/15679415384.pdf In PDF document text
    • http://mdsalon.ru/img/lib/file/27869576803.pdfIn PDF document text
    • http://lysfyyy.com/upload/files/35251941207.pdfIn PDF document text
    • https://propiedades.net/ckfinder/userfiles/files/99867059131.pdfIn PDF document text
    • http://ulrike-mayer.de/userfiles/files/dasedogogunamejik.pdfIn PDF document text
    • https://harkakotony.hu/UserFiles/file/joxatisadonunenotiva.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/33264d857ce81ffb2ce633dde4a3344d/19927401202.pdfIn PDF document text
    • https://roshnaai.com/ckfinder/userfiles/files/gerixalol.pdfIn PDF document text
    • http://uzmansporzeminkaplama.com/resimler/files/41958725659.pdfIn PDF document text
    • http://thesprotia.gr/uploads/file/gewajebufelugak.pdfIn PDF document text
    • http://zsmnowakowski.pl/userfiles/file/7290049194.pdfIn PDF document text
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161315667ea7d2---61852960667.pdfIn PDF document text
    • https://yantrasearch.com/ckfinder/userfiles/files/zafize.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16132195446c78---desurifemojukekobumevesu.pdfIn PDF document text
    • http://sonhanint.com/uploadpic/sun/files/202109091405107599.pdfIn PDF document text
    • http://hak-al.com/resimler/files/77817658581.pdfIn PDF document text
    • http://goldenteriyaki.com/uploads/files/pezixukutiline.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613352489718a---4763671403.pdfIn PDF document text
    • http://yugang360.com/upload_fck/file/2021-9-5/20210905185818775064.pdfIn PDF document text
    • https://rybczewice.pl/userfiles/file/84663986094.pdfIn PDF document text
    • http://baruraprotidin.com/assets/ckfinder/core/connector/php/uploads/files/semujib.pdfIn PDF document text
    • http://mindentudor.hu/userfiles/file/zusatup.pdfIn PDF document text
    • https://hw-power.com/uploads/ckfiles/files/613f072b64ab5.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=what+is+flagship+smartphonePDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b20e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB20E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA20 15032 bytes
SHA-256: aa53cb9518f297fd3d9aa87140b29d9162a3efca9be8f17b22171fc85c12ed74
font_02_sfnt_off0000efef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFEF 10796 bytes
SHA-256: daa9bc2d49bd348af8fccfd1c4ade863d323607b617ee6403395e471cbb70bdf