Malicious PDF — malware analysis report

Static analysis result for SHA-256 331736c3d6f0fb51…

MALICIOUS

PDF

85.5 KB Created: 2021-07-15 12:31:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9df67f2956a3847d12723d25c76e20fd SHA-1: ea8ce1e4b241fe8371ea2522c7c25f65e8bb68f0 SHA-256: 331736c3d6f0fb5164b79cd547ccab0e84a6bf565ad1f0035c92f7adf1441939
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is identified as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm. It contains numerous URLs pointing to compromised WordPress sites and disposable storage, suggesting an attempt to lure users to malicious content. The presence of external URI heuristics and link farm indicators strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://dixietemporarystorage.com/wp-content/plugins/super-forms/uploads/php/files/e2230b7c87fdd46dfc2a82f1953bc1b1/vadunakoxoko.pdf
    • http://taikenplan.jp/ckfinder/userfiles/files/19747896981.pdf
    • https://cald-lighting.com/wp-content/plugins/super-forms/uploads/php/files/8e7a309683561a3f36976827276f399e/puturofe.pdf
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160799ef1a8d93---dukepun.pdf
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095bee49e82d---kenofeput.pdf
    • http://flygarfield.net/userfiles/file/bijudoxajuzebufotawep.pdf
    • https://www.pal-kont.hu/wp-content/plugins/super-forms/uploads/php/files/f6e61250d4b71d158502b79b1bc3b5ed/kokotibupekotilapukalugen.pdf
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/16092e416ad878---kunidud.pdf
    • https://www.engltg.com/wp-content/plugins/super-forms/uploads/php/files/d928d0255769bb99d6fb3e635429db2d/1816404749.pdf
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075925f442d3---buwedixofifojej.pdf
    • http://nessium.fr/userfiles/file/mesozisok.pdf
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/16076ba4724f97---60351508065.pdf
    • https://ljlconst.com/admin/images/file/mevipefewen.pdf
    • https://contabil-fiscal.ro/mm/file/92424919335.pdf
    • http://fandimnarodaku.cz/upload/file/6144788157.pdf
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e68beac6f0---revejekumokifefafufejid.pdf
    • https://jiptv.nl/wp-content/plugins/super-forms/uploads/php/files/d00e6nvhtq9j3aclq2gukr6s4e/80322069910.pdf
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d937347d56b---woduxakekikegux.pdf
    • http://asiancfea.org/userfiles/file/30651644183.pdf
    • https://cambodiaangkorhomestay.com/userfiles/file/68742444748.pdf
    • http://josephlillianmorrisfamily.com/clients/59960/File/58718761260.pdf
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160752a1f0b1a5---naxasixesubutafawenam.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160986f2d1d561---resukelep.pdf
    • http://yummyschool.com/_UploadFile/Images/file/tapixakefajiges.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=bad+tooth+nerve+pain
    • 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_off0000ee8c.bin
587398cc31a62112fbcea63379aaef4f42fe174b09655e07a8cb1945e2d9f392
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE8C 16484 bytes
font_01_sfnt_off00011952.bin
3929996b39057e9ecd4170ed115396badd02305b8d43723c16f4745de7eabaf7
pdf-font-stream PDF embedded font (sfnt) at offset 0x11952 10396 bytes
font_02_sfnt_off000130c2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x130C2 16792 bytes