Malicious PDF — malware analysis report

Static analysis result for SHA-256 5bb5862862dc3e13…

MALICIOUS

PDF

78.3 KB Created: 2021-08-25 09:13:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 638af9a7cb8484dca0993489e6586d83 SHA-1: 7f1513e9c550ed8071bb80e7dd6f29364d8cedbb SHA-256: 5bb5862862dc3e13b680026fb6fc873b2f9b2efa3cf9854543c524fc8b331db5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct content clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 http://chochosanencino.com/uploads/files/85746076547.pdf In PDF document text
    • http://rapet.hu/files/73797458527.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160869c299766d---82724410436.pdfIn PDF document text
    • http://diamantina-joaillerie.com/ckfinder/userfiles/files/91013824639.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/s6ebub07mc6qkq205e09hijfb4/zunosiramitixi.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/72799939187.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160bc167bbed4b---31856031557.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/ggdiaao008m2ep1bh6atb81qke/zovinolezotegiwefof.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d3d3e0d4cde---gixubewanebizipajanu.pdfIn PDF document text
    • https://www.couleurs-et-jardin.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160f25683ad787---96932510005.pdfIn PDF document text
    • http://yamamatoen-wanwan.jp/ckfinder/userfiles/files/47568846409.pdfIn PDF document text
    • https://nikosdimos.gr/userfiles/file/vowudukodufozobuguburofe.pdfIn PDF document text
    • http://klhl.com/userfiles/file/60744895461.pdfIn PDF document text
    • http://ahlhy.com/uploads/file/272335509959.pdfIn PDF document text
    • https://propactionvehiclesuk.tv/userfiles/files/35608602532.pdfIn PDF document text
    • http://chretkinia.pl/userfiles/file/74822432331.pdfIn PDF document text
    • https://spcinternational.in/ckfinder/userfiles/files/kojuveminetakilixogi.pdfIn PDF document text
    • http://pm-ural.com/uploads/files/54781624735.pdfIn PDF document text
    • http://maroba-zirndorf.de/file/lijukene.pdfIn PDF document text
    • https://electrabicycles.pl/app/webroot/uploads/file/16209506047817.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/rsh48da1g5dhdd1e4bkl27h8ek/90278456162.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=intersection+of+two+spheresPDF 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_off0000ceed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEED 17212 bytes
SHA-256: 31ceed03c7f64219f80e3fd10b00ad61f975cc0d93e32ff071a696ae638ba04e
font_01_sfnt_off0000fc84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC84 10404 bytes
SHA-256: 6c73816ab665565a94ad8b2e4c99fe5f17ca82cefa7d493e179d01114fdef72d
font_02_sfnt_off00011421.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11421 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1