Malicious PDF — malware analysis report

Static analysis result for SHA-256 1056da40318deb18…

MALICIOUS

PDF

79.1 KB Created: 2021-09-18 12:18:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c0203efb139c0ca945d7e53f91f7459d SHA-1: c28219ccb321565ab377fc98beb39f9f4773942e SHA-256: 1056da40318deb18e9f3df6ac814eee30e8a40121aa1baab60611f99dee512f5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of multiple external URIs and link farm heuristics supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://nomylo.ru/uplcv?utm_term=how+to+lock+phone+by+imei+number PDF link annotation
    • https://sensiblemachines.com/ckfinder/core/connector/php/files/28485096752.pdfIn PDF document text
    • http://laduses.nl/image/file/83825125790.pdfIn PDF document text
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/d948930a90df5f1133de2fc857018fa4/dubaxusavunuvidafuzusudef.pdfIn PDF document text
    • http://brucemayrockinstitute.com/assets/ckfinder/core/connector/php/uploads/files/gavolonusewepivibev.pdfIn PDF document text
    • https://netkat.in/ckfinder/userfiles/files/23294431516.pdfIn PDF document text
    • https://sunsetlearningcenter.com/userfiles/file/xivetexito.pdfIn PDF document text
    • http://kondicionery-dolgoprudny.ru/upload_picture/file/74784271399.pdfIn PDF document text
    • http://vector-luczak.pl/new/fck_user_files/file/tivexupizeworowuga.pdfIn PDF document text
    • https://media-get.com/userfiles/files/vojojofegusabex.pdfIn PDF document text
    • http://studiomontironi.eu/userfiles/files/79241312303.pdfIn PDF document text
    • https://vicotelecom.vn/static/source/images/file/dededuzasidigadi.pdfIn PDF document text
    • http://achilleferolla.it/userfiles/files/jafawalatuxonepevirase.pdfIn PDF document text
    • http://asbufestival.com/uploads/FCK_files/file/58705366868.pdfIn PDF document text
    • http://2016.letnifestiwal.pl/ckfinder/userfiles/files/wenubenanoloxit.pdfIn PDF document text
    • https://pleasanton.com/wysiwygfiles/file/teruriwebilop.pdfIn PDF document text
    • https://rcvizovice.cz/ckfinder/userfiles/files/dipasuj.pdfIn PDF document text
    • http://tungalag.mn/userfiles/files/kujejifudelinozutozefidi.pdfIn PDF document text
    • https://polenhosting.com/calisma2/files/uploads/nulirugisusuragesif.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/1612ebbf21234c---250484002.pdfIn PDF document text
    • http://zsdbiopharm.com/upload/files/46617057201.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/51756e7160fe7ba5e1b55e2c91fd027e/sonubivezajinilomuvakubo.pdfIn PDF document text
    • https://webmenuplus.com/images/file/vikuxulakado.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-9-16/20210916112400605342.pdfIn PDF document text
    • https://piti.leaddeehub.com/userfiles/files/mibemipukefogudo.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://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_off0000d1cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1CF 10832 bytes
SHA-256: e222ffc75e5b62f6374537855f557b8eb73281e805efb937e3af5ef8210833ed
font_01_sfnt_off0000ea5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA5B 16852 bytes
SHA-256: 7a9da433299f378f93c5b877589e5ffa020ed511d8e40e251a1d9b5d519d50ed
font_02_sfnt_off000116aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116AA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1