Malicious PDF — malware analysis report

Static analysis result for SHA-256 696634c8bd2ba66f…

MALICIOUS

PDF

73.3 KB Created: 2021-09-27 22:55:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 2ed505021eacc98da3a1a0b15311f4af SHA-1: fd7dfea8cfd52700b9d4f3ebcdb0642c38fb5c94 SHA-256: 696634c8bd2ba66fb69a9e942e1f06f5ae9060673b8c0292e56bff6799565116
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to other PDF files hosted on a variety of domains, many of which appear to be disposable or low-reputation. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a pattern of using small PDFs as link farms on disposable hosting, suggesting an attempt to distribute malicious content or phish users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • 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 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://weddingdove.tw/uploads/files/202109060155514581.pdf In PDF document text
    • https://wcfkenzi.com/ckfinder/userfiles/files/dibetuwobigiguzezari.pdfIn PDF document text
    • http://fabtur.ru/upload/files/31632181908.pdfIn PDF document text
    • http://rigosarchitects.gr/userfiles/file/wemibasugivesomeroniseto.pdfIn PDF document text
    • http://hakanhurdacilik.com/userfiles/file/bufemetiboregafuritafefo.pdfIn PDF document text
    • http://maxidmum.com/images/upload/fck/file/45266517331.pdfIn PDF document text
    • http://bloemenwinkelindex.nl/images/uploads/33657267653.pdfIn PDF document text
    • http://abbeytraining.net/userfiles/file/82553895806.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/1615212a393a6b---basefivi.pdfIn PDF document text
    • https://delphin-restaurant.com/ckfinder/upload/files/37409369070.pdfIn PDF document text
    • https://bselink.com/userfiles/file/69508851621.pdfIn PDF document text
    • http://jindi2010.com/uploadfile/files/53806516395.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-9-16/20210916221614554342.pdfIn PDF document text
    • http://jumpstart.mobi/userfiles/file/xegifuzuributomaposur.pdfIn PDF document text
    • https://hbfilm.ca/resimler/files/folugovijedubovapevo.pdfIn PDF document text
    • http://fashionflutters.com/ckfinder/userfiles/files/40053630178.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/bpr3kg77l336f0s5dkddphmikn/72804157343.pdfIn PDF document text
    • http://air-ned.com/uploads/files/mumolidovogebotijug.pdfIn PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/pemubele.pdfIn PDF document text
    • http://websurin.net/UserFiles/File/56760861444.pdfIn PDF document text
    • https://anjingliar.com/contents/files/34172462923.pdfIn PDF document text
    • http://hosungtour.com/FileData/ckfinder/files/20210922_26E0D3511635327F.pdfIn PDF document text
    • https://studiovizia.com/webroot/img/content/files/kunesaja.pdfIn PDF document text
    • http://vitalenzyme.com/uploads/fckupload/file/jerulalaxuputagawimu.pdfIn PDF document text
    • https://strategie-forex.com/ckfinder/userfiles/files/nafutolefukaxadusiw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+sign+out+from+onedrive+in+androidPDF 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_off0000b9c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9C4 17392 bytes
SHA-256: 1415e19b2f6279d06c0532e28f498f7bde792b6508a29d56d5829bdddc7ebf42
font_01_sfnt_off0000e63a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE63A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fe51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE51 10896 bytes
SHA-256: c3a7a0d10d13d520499a313ca328979f283ac492e2119ab766fa09a7ee359474