Malicious PDF — malware analysis report

Static analysis result for SHA-256 05c9ca724d58f925…

MALICIOUS

PDF

82.3 KB Created: 2021-08-23 14:04:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 1df2cb198bcd349e212c1255748e03b3 SHA-1: 4c94ee140de46a25a2919941bfe1410f25edc7e9 SHA-256: 05c9ca724d58f925a592dded16c8d1a632c8807f55213bfaf1dbf428ca67e8f8
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised or disposable hosting sites. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and detection results strongly suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://shukokai-voves.fr/userfiles/file/fevepimabiburigutaxufijer.pdf In PDF document text
    • https://gofropack.com/wp-content/plugins/super-forms/uploads/php/files/55aa238542f29f51400f174f05693f94/92978663270.pdfIn PDF document text
    • http://kiajihlava.cz/UserFiles/File/didareronika.pdfIn PDF document text
    • http://csc010.com/userfiles/file/20210706011144_i5kkhx.pdfIn PDF document text
    • http://janjoling.com/public/ckfinder/userfiles/files/50665521975.pdfIn PDF document text
    • http://tlumacz-lipno.pl/pdrzewiecki/files/nipuj.pdfIn PDF document text
    • https://thaihoanghung.com/upload/files/kanikufasebagefitekinedav.pdfIn PDF document text
    • http://panyuchen.com/ckfinder/userfiles/site_eachfun_com/files/nemaxujufaxutat.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/47b0fedbe88bc9729a5d1dd52cf3d21c/9515272851.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160838c9106fd6.pdfIn PDF document text
    • http://munnarinfo.in/userfiles/file/92259934002.pdfIn PDF document text
    • http://regcureguide.com/files/files/16614093803.pdfIn PDF document text
    • http://bethelcommunityone.com/clients/880032/File/29609807017.pdfIn PDF document text
    • https://marbellamohali.com/wp-content/plugins/super-forms/uploads/php/files/68b5c43dd5d3dca971fc6d795bbeac2b/27812003311.pdfIn PDF document text
    • https://kalyna.ua/sites/default/files/userfiles/file/63843269291.pdfIn PDF document text
    • http://azizolace.cz/images/file/53825497273.pdfIn PDF document text
    • http://scales-center.com/shop/fck_file/file/51672679656.pdfIn PDF document text
    • http://scales-center.com/shop/fck_file/file/13499063175.pdfIn PDF document text
    • http://primebrokeragetx.com/ckfinder/userfiles/files/zonawagetesufivawad.pdfIn PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/160fb9d2c2679a---jufujetovokuxogetox.pdfIn PDF document text
    • http://kiszelyugyvediiroda.hu/docs/file/912459810.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160772f7cc0b95---76034978859.pdfIn PDF document text
    • https://ajur.rest/uploads/userfiles/file/9417930958.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/2d8e9cd2c69be3d0667c0629c5e076a7/sewopat.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=zakat+to+brotherPDF 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_off0000e1cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1CC 16916 bytes
SHA-256: 43a4b1b6d84905effa89c8ebf038dcc93ed25bc9974f4925544d16cadb23f504
font_01_sfnt_off00010dba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DBA 9988 bytes
SHA-256: 7a993f33fa1490ddfe15520311b7a5c6c04d7ef5ab07a6ba930ae2df6304b382
font_02_sfnt_off00012416.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12416 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1