Malicious PDF — malware analysis report

Static analysis result for SHA-256 341793f3c642781a…

MALICIOUS

PDF

85.6 KB Created: 2021-06-28 10:50:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: c1f79168a5e25df5b671813edcb6dc9c SHA-1: 4107e727b031987209a6c361eed8f55da52bb67c SHA-256: 341793f3c642781aa9fe5496d18ef9b13151970b8f6b502d35032809b1e82759
156 Risk Score

Malware Insights

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

This PDF was identified as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous URLs that point to compromised CMS upload directories. These links likely lead to further malicious content, such as phishing pages or malware downloads, indicating a multi-stage attack. The presence of multiple distinct hosts and the use of 'utm_term' parameters suggest an attempt to obscure the true malicious infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609841e5c679e---56389827586.pdf In PDF document text
    • https://unosms.us/userfiles/file/miroloxewovori.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160754e14aa51a---97937689823.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/mqt4ci73j0lurkbbia12h9ue6f/volebijowulexorezu.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcb7cfa7319---nakunixidobe.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082bd2139334---40195967071.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/16078629d4db12---16340635096.pdfIn PDF document text
    • http://webcertain.net/contentupload/fckeditorUploads/organization_/file/74757644024.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16086e244ace38---78894630073.pdfIn PDF document text
    • https://dm288.rs/slicice/file/49703329513.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/hsshg8kh921n4vfj9t3hip8oc1/27907090060.pdfIn PDF document text
    • https://beautyyaurient.com/editor_upload/file/donutumewedukunexabijiw.pdfIn PDF document text
    • http://simonide.org/userfiles/file/xiradokunutenimawobe.pdfIn PDF document text
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/a41a1ee1ae51050818af8f5a294fcfd0/tejepejupenanobeloja.pdfIn PDF document text
    • https://cihangirhotel.com/upload/ckfinder/files/wowikevobasasexonedima.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/7db6551a66d9a5a6fc922478ff0dbc3d/supufugomawipararumajegoz.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3986347065---22954122962.pdfIn PDF document text
    • http://chingyi.tw/userfiles/files/ziborebifujokon.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160c5c04be9322---31405741739.pdfIn PDF document text
    • https://medtek.vn/storage/file/20049427371.pdfIn PDF document text
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/ca900cff880ca7913904c394f69792a1/46521674340.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c34f04d72b3---zinuseworoxirenewuzonef.pdfIn PDF document text
    • http://tamker.hu/userfiles/file/xopovigobojigasodulu.pdfIn PDF document text
    • http://cintabogor.com/Uploads/userfiles/files/sinikizapede.pdfIn PDF document text
    • http://m2mus.ca/clients/b/b1/b1ca46fdb12d68e762e4a8b3318caec0/File/4766842956.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=ocr+apps+for+macPDF link annotation
    • http://s292376414.onlinehome.fr/datas/imgmail/file/47398045673.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_off0000ece9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECE9 10192 bytes
SHA-256: bf62f6ae236c5a3348f0e1fdb73ce8c61be72fa6750948e5cd345140112d92a6
font_01_sfnt_off000103c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103C6 17468 bytes
SHA-256: cdc763abf0fee89533c8e0048a4a40d1d3ddd4c12a2bb2666542b3e476d5c018
font_02_sfnt_off00013137.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13137 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1