Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a91b5d02d396b8a…

MALICIOUS

PDF

76.1 KB Created: 2021-09-02 09:18:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5f4998dab0a5de0cfeb4b88627611733 SHA-1: c375417df86ff8ec79ee958d09a35948742c14bd SHA-256: 6a91b5d02d396b8adcb6a55e24252b2fddafa2af2e9b5ce329c1ec50ee1ba350
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of an attempt to exploit users through deceptive links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://pistant.ru/uplcv?utm_term=introduction+to+the+theory+of+computation+michael+sipser+solution+manual
    • http://ballmillfactory.com/d/files/jijetulorat.pdf
    • http://boilerservis.ru/uploads/files/49815044064.pdf
    • https://aedwea.com/upload/foto/bakajufejaniwar.pdf
    • http://dpsszczytno.pl/photo/file/94143878396.pdf
    • http://host.keraladreamhomes.com/~viswabrahmathach/admin/fckeditor/editor/filemanager/connectors/php/userfiles/file/pixodepovuginawupet.pdf
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/6d7da30a779e406be68ce7a455012c41/32038061131.pdf
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609f08e88e063---84538531721.pdf
    • http://abwsalisbury.com/uploads/files/lelomonotikejun.pdf
    • https://ontech.vn/images/ckeditor/files/53077447544.pdf
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091b6d100bfa---lilisamuk.pdf
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608bd38877580---jivusemasubu.pdf
    • https://fzclicks.com/demo/files/editor/file/86907942929.pdf
    • http://hataylezzeti.com/resimler/files/tejotujituvuxovufadato.pdf
    • https://naoshima-habitant.com/xenew.pdf
    • http://sireny.net/share/files/98792500482.pdf
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/160c263fb0f601---ruwanojima.pdf
    • https://salwangurugram.com/files/66749532360.pdf
    • http://qiuyutv.com/userfiles/files/20210603093558.pdf
    • http://atenngo.com/admin/sites/site/documents/regunekasike.pdf
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/62a878c5cc85951477d2f4b75a98efd9/zakifejiwojetoz.pdf
    • https://vandolderskb.com/images/usr/zikavofo.pdf
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/s6uiepu6d0homheegb21gqbvu8/towelemimifef.pdf
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095e08736b66---fogumovogupo.pdf
    • http://nw-line.ru/generic/uploaded/wolareniz.pdf
    • 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_off0000be0d.bin
31bd45e67a9939e30d9e5fff362cfd873fc2dca2eeb1230f6e30bdf2c2c8fef0
pdf-font-stream PDF embedded font (sfnt) at offset 0xBE0D 18100 bytes
font_01_sfnt_off0000ed56.bin
5d671684c215ab7d7792dd370b70a18766bfb0a100f7f7b2d0b012aa23a589e3
pdf-font-stream PDF embedded font (sfnt) at offset 0xED56 11052 bytes
font_02_sfnt_off000106e6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x106E6 16792 bytes