Malicious PDF — malware analysis report

Static analysis result for SHA-256 d21a8c6db45eae0c…

MALICIOUS

PDF

84.5 KB Created: 2021-10-13 15:48:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: f093e9b86e36d45a36243bc84fb8d7cb SHA-1: 8eb558e15ea0f07483a67bb2ceeae38e6dfca587 SHA-256: d21a8c6db45eae0cf2be43c35bbde8e9a6bcfd98ee33a620ee28eed689edb1c1
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically highlights the nature of the links as a link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://3e-recycling.ru/app/webroot/filesfiles/44717004569.pdf In PDF document text
    • https://aventura-agence.lu/userfiles/files/nulawigomogaji.pdfIn PDF document text
    • https://architektor.ru/uploads/file/79467508746.pdfIn PDF document text
    • https://at2-turbo-j3t.com/contents/files/14662691917.pdfIn PDF document text
    • http://www.sport-konyv.hu/userfiles/file/vuganizokuzobuvipitovo.pdfIn PDF document text
    • https://aviatroglo.fr/IMG/file/77448318127.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/30861320180.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139ff9deed06---1049913343.pdfIn PDF document text
    • https://horizontire.com/userfiles/file/fozur.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/161643d50ec0d8---61079789667.pdfIn PDF document text
    • http://stihoplet.by/upload/editor/files/devodexefe.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/4d40f21d77726172c2bc23003086e91e/40571533427.pdfIn PDF document text
    • http://ghespanail.com/fckeditor_userfiles/file/31975455442.pdfIn PDF document text
    • https://arenerachicamocha.sinecsas.com/ckfinder/userfiles/files/mawemiri.pdfIn PDF document text
    • http://sydjpg.com/images/upload/file/20210910_151448_178.pdfIn PDF document text
    • http://balone.net/_upload/file///4452000278.pdfIn PDF document text
    • http://kechengchem.com/upload/files/luwigazufepupasozuz.pdfIn PDF document text
    • http://gaongonmaiphuong.vn/webroot/img/files/gitabo.pdfIn PDF document text
    • http://cautrucpalang.vn/webroot/img/files/34084926496.pdfIn PDF document text
    • http://hzhuacui.com/images/upload/File/bawolisutonirajade.pdfIn PDF document text
    • http://195exim.com/datas/files/siligupegisake.pdfIn PDF document text
    • http://shengnabei.com/uploadfile/file///2021101314305712.pdfIn PDF document text
    • http://sahrugs.com/userfiles/file/dumojoni.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/bfdcd8573l0tkn55muhrgfpde1/57503459652.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/23D8k0Ec_6w/uplcv?utm_term=the+highwayman+textPDF 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_off0000e6b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6B1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fec8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEC8 10388 bytes
SHA-256: 4ea65e734be6c31352bc19818794c04bc29e0231258a1c61a2b8dfc04a11fc3c
font_02_sfnt_off0001162d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1162D 18332 bytes
SHA-256: b17b04c9d8d304c59187c5640fa588de5cc4084f9958c06a0bec67f5b9053abd