Malicious PDF — malware analysis report

Static analysis result for SHA-256 0156b5e3db1b81c5…

MALICIOUS

PDF

88.8 KB Created: 2021-09-05 08:21:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: aa72f29117e4894e390d5418a3640ade SHA-1: 91cc6cbe9ef243146b3cd427845b82c8ba11a351 SHA-256: 0156b5e3db1b81c5f3ca84321ece8e5f5ca2ceabc5c2fbb27e334e82dcc405ab
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF file contains a link farm pointing to numerous URLs, many hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The document body is unreadable, but the heuristic firings and numerous extracted URLs suggest the primary purpose is to redirect users to external, potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/5de20b9cd56e55aeeed4f3f3315244bc/lininewijerowapi.pdf In PDF document text
    • http://cn-junsheng.com/upload/file///20218223638453.pdfIn PDF document text
    • http://cbestdesign.com/ckfinder/images_store/files/27917478396.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/bceb8fdd7e8f45c191c77a642a7cea3f/takomalex.pdfIn PDF document text
    • https://mides.vn/images/ckeditor/files/39224489274.pdfIn PDF document text
    • http://ashioke.com/images/library/File/kipimokiviwapewulisuwu.pdfIn PDF document text
    • http://domgr11.ru/uploads/files/luwawalekenasirofoj.pdfIn PDF document text
    • https://ringid.vn/ckfinder/userfiles/files/29474098135.pdfIn PDF document text
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/52320811340.pdfIn PDF document text
    • http://viral-list-monster.com/ckfinder/userfiles/publics/files/43923271220.pdfIn PDF document text
    • http://sjanzee.nl/file/zaremapotawaxifezed.pdfIn PDF document text
    • http://kapsalonvogue.nl/files/file/gulini.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610cd15d74690---1747964673.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fbe6ae6ca17---31591553208.pdfIn PDF document text
    • http://hebammenglueck.de/ckfinder/userfiles/files/41316384654.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b3b6bdfc43---misug.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16090f8b1c8728---bofafudizaxutuvijono.pdfIn PDF document text
    • http://alexsrmenchion.com/clients/b/bf/bf5401b25fe3457642f5a6f1150d5537/File/zibinanogiso.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160db256767b1c---55282369527.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608858669c4cd---3040238434.pdfIn PDF document text
    • https://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/cb0ef06porhfbojjvf26chpbdu/74505530784.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/7516ff823bb5c951d2452c426e054b2c/70843324503.pdfIn PDF document text
    • http://metabolit-plus.ru/files/file/25224154044.pdfIn PDF document text
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/eff740b766fd57f3b5d6fcaae1c61a63/56904153555.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/irv1nfpbbvvc2t56ajbsb030m2/76584222009.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=kojiki+donald+philippi+pdfPDF 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_off0000f62b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF62B 18456 bytes
SHA-256: 9867b111436dc6b9492a5b1e22ef5d8b0058d10fca60eb7c95a26ce887ce3d3f
font_01_sfnt_off0001266b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1266B 10312 bytes
SHA-256: e106c596cf7dbaedf8ed2237884b696e06e3a7999fe70a188b04c9976af47608
font_02_sfnt_off00013d67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D67 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1