Malicious PDF — malware analysis report

Static analysis result for SHA-256 37e77e37e5098fa1…

MALICIOUS

PDF

92.4 KB Created: 2021-06-26 05:42:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 109b36e1a08c6ac98af2ce587c2dfab9 SHA-1: 2675e9de45d7a2f4de2becb8b188ccaa3df90086 SHA-256: 37e77e37e5098fa1d09c9819ab13749e9a08cd6cfaac9072a82a2de3e1cb8fe3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised websites, likely intended to trick users into downloading malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent, with the links suggesting a phishing or malware distribution scheme. No scripts were extracted, but the presence of numerous URLs on compromised domains is a significant indicator of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

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://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/hkmmp6f8q6jt07np8udq87k190/vizojomisutovelofus.pdf In PDF document text
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/aashep8ritftkgj7onhfaji894/88310338086.pdfIn PDF document text
    • http://jvcc.cn/ckfinder/userfiles/files/210614182250592108zfmkf.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160704e605c1d6---80919221550.pdfIn PDF document text
    • https://smartcirclegroup.com/userfiles/file/ludajidesaf.pdfIn PDF document text
    • https://xlspandoek.nl/userfiles/file/14956725425.pdfIn PDF document text
    • http://drstevealbrecht.com/wp-content/plugins/super-forms/uploads/php/files/c5531e384bac9401913c84c22cc1e126/tevinofupenuwodidukifig.pdfIn PDF document text
    • http://cravaluos.com/ckfinder/userfiles/files/38558760676.pdfIn PDF document text
    • https://big-cash.de/wp-content/plugins/super-forms/uploads/php/files/6hnrg6c9t9euda9ni6jk1jqoa4/zomisifapera.pdfIn PDF document text
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/bbbb99daca4eee0ab26539aba69a66a6/16234540223.pdfIn PDF document text
    • https://europeancustomtailor.com/wp-content/plugins/super-forms/uploads/php/files/26a1ec3ed83d70aa4071cd52c3a1a208/52015774460.pdfIn PDF document text
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607df5fba5935---xamijipudufebigasixigo.pdfIn PDF document text
    • http://tpdw.pl/userfiles/file/vituzi.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/e60a6a61201fe92c8c73d9269477e8a2/7784418958.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/si1the1jcl4cfl84tdtn3rmkkl/bivuseba.pdfIn PDF document text
    • http://catgarner.com/clients/873270/File/96934533061.pdfIn PDF document text
    • http://zoncmswebsitebeheer.nl/files/editor/file/jedojikunosesupuveviwiguw.pdfIn PDF document text
    • http://iphysiology.ru/upload/47743461395.pdfIn PDF document text
    • https://plswa.com/wp-content/plugins/super-forms/uploads/php/files/5aa56f62692122d342fe1d6d27adef13/16318566979.pdfIn PDF document text
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/f9a7f87113891b7c68ce8856871abe00/52321385965.pdfIn PDF document text
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160732b36d59d3---lawugusipojekuxosu.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/e2b5c40f4b83e76c612a4fa789d89464/wejude.pdfIn PDF document text
    • https://admonks.ru/wp-content/plugins/super-forms/uploads/php/files/9d4ae4139a0bf7ba81016fa63fafe693/38909687086.pdfIn PDF document text
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/1d8fd2729ac07be3770b76eadb6bf64f/6043066171.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa736dce3eb---94987812864.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=photoshop+cs6+serial+number+for+macPDF 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_off0001056f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1056F 11156 bytes
SHA-256: d2da74253fcc75bc834ce33a5cb4bfa225c899472887e09e934f4ce0383c005e
font_01_sfnt_off00011f1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F1D 17288 bytes
SHA-256: db439609d10d2521e24dfb181777b94d02d045c94ffb300b8f50411eab01c1e5
font_02_sfnt_off00014c39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14C39 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1