Malicious PDF — malware analysis report

Static analysis result for SHA-256 e24a38d30fd73dc0…

MALICIOUS

PDF

82.5 KB Created: 2021-09-23 20:33:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 434eebfd5c20367ce60330535c541f30 SHA-1: 75ff39b348f2640163cf4125671418e395dcc5fe SHA-256: e24a38d30fd73dc0e157ca773dffbbbc8090bd8aa1a6b3da70cf20c14a98e16b
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to various domains, many of which are associated with compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate 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 0.9964

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://fu-xin.tw/uploads/files/202109172316316274.pdf
    • https://k85shj16h-561lt.com/contents/files/bapidonijo.pdf
    • https://bayihoki99.com/contents/files/gemotosojem.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16147ab9617193---pugikejokeremijukulopuzor.pdf
    • http://global-gypsum.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146c0a76c57f---kifururazuzukufovova.pdf
    • http://mrspk.com/ckfinder/userfiles/files/91668268461.pdf
    • http://cimkezes.hu/uploads/ckfinder/userfiles/files/kesut.pdf
    • http://olgapolyakova.de/files/files/61013199719.pdf
    • https://bosingels.nl/ckfinder/userfiles/files/37137995268.pdf
    • https://koltoztetes-szallitas-lomtalanitas.excore.hu/ckfinder/userfiles/files/80832038169.pdf
    • http://eco-building.cz/UserFiles/File/levosenuradapelutek.pdf
    • http://uralcomservis.ru/crn_fls/crn_files/mexavus.pdf
    • http://pileshoppen.dk/userfiles/file/gudularitebenib.pdf
    • https://bitree.com/ckfinder/userfiles/files/vunogejipizojazuwotalela.pdf
    • http://jlsxjy.com/right/UploadFile/file///2021091605555073499.pdf
    • http://dxqzx.com/ckfinder/userfiles/files/20210901_175150.pdf
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/3ufr3487e7hskkgcbpb8f30844/kevovupuj.pdf
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dbc1836edb---giduwikevi.pdf
    • http://dorp.pl/userfiles/files/rivudepabonazatoxoromid.pdf
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/c0b6a697a35938f0cc26ed76ccd7012c/46838292295.pdf
    • http://aeon-dev.com/uploads/files/202109010607543911.pdf
    • http://felixefontesadvogados.com.br/ckfinder/userfiles/files/81073083604.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=set+multiple+timers+android
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dcd3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDCD3 16792 bytes
font_01_sfnt_off0000f4ea.bin
03f89ac5e1dce1258b02614c7388a63676c50c2c5c68ad96b27aeb7542e3a4ea
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4EA 10728 bytes
font_02_sfnt_off00010d72.bin
2ae76d9fa6c8342b12986cb09597404c28db42bbf6f30bf65128ec09c6a81052
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D72 17896 bytes