Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5e6001d9de19d53…

MALICIOUS

PDF

122.0 KB Created: 2021-09-04 06:21:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b7a727092b32623e622cc3d26e055167 SHA-1: 8c803a861d2069aa820e0acb321b7b96b25c0a86 SHA-256: a5e6001d9de19d5398f4cfb38f05c498f87dafd8e96a5d2788fd57df887035a9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users to potentially malicious content. The document body is heavily obfuscated and unreadable, providing no direct clues to its intent beyond the presence of these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://ivankotov.ru/img/lib/file/pelalud.pdf In PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/1607d86a93b0bf---sebuluruva.pdfIn PDF document text
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609b636f90a1b---61101755338.pdfIn PDF document text
    • http://ahdongjiu.com/upload_fck/file/2021-4-29/20210429023023383220.pdfIn PDF document text
    • http://kiuruvedenlukio.fi/tiedostot/file/pukakuwatififu.pdfIn PDF document text
    • http://mppscstudy.com/admin/usercontent/file/63547838249.pdfIn PDF document text
    • http://swaminarayangm.org/userfiles/file/6963058877.pdfIn PDF document text
    • https://solidpractise.com/files/userfiles/file/56475822545.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/0b8ff2c77ae982a08025d8336d003122/sutubosiz.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/16073cb45f1051---45793765976.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dfabebc610b---bobewodetijojejefosa.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d3cf48d3f8---lagekoxiverubuwewoliwu.pdfIn PDF document text
    • http://newgrids.com/userfiles/file/safedasavo.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160854bced0e43---90081682410.pdfIn PDF document text
    • https://biovuspharma.net/userfiles/files/wubixitevuvulabogulewixaz.pdfIn PDF document text
    • http://kperrylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sisegixeximuvolemabi.pdfIn PDF document text
    • http://urbanconstructions.org/images/uploadedimages/file/sudawijokolevutazogog.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/juzojeriwaratedajivemezav.pdfIn PDF document text
    • http://aa-nusd.jp/vanupezug.pdfIn PDF document text
    • http://forti.in/userfiles/file/98249002984.pdfIn PDF document text
    • http://frigotechreina.com/userfiles/files/29765908104.pdfIn PDF document text
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/65706920bb0b980884a8c0da79cd4d0f/45183625150.pdfIn PDF document text
    • https://dcimx.com/files/38849488693.pdfIn PDF document text
    • http://zatuchlina.cz/upload/file/72948732536.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=2019+abituriyent+jurnali+ballar+pdfPDF 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_off000169b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x169B0 24760 bytes
SHA-256: f3de61556798faffc9e6695ab0d9daf41da9dbf144c13d1f9fc0985de45f3244
font_01_sfnt_off0001a873.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A873 11052 bytes
SHA-256: a4bbfe71969d11eb578cf45efc02a1b54fa4dc00337474ce86a425675098e1f3
font_02_sfnt_off0001c230.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C230 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1