Malicious PDF — malware analysis report

Static analysis result for SHA-256 c83c4429f1c995bc…

MALICIOUS

PDF

69.9 KB Created: 2021-09-03 08:01:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e0053d3597231a122c9a6b905b585f0a SHA-1: 737001ea0978cb62af58773eaead3e5ee9595f8f SHA-256: c83c4429f1c995bcf7869ee4f8649fe2aa656139a9acef24ec9ac81b8e3b3d48
156 Risk Score

Malware Insights

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

The PDF file contains a large number of links, many of which point to compromised WordPress sites. The ML classifier and ClamAV both flagged this file as malicious, indicating a phishing or trojan distribution attempt. The primary function appears to be redirecting users to external sites, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/0ct7sbgeat4ib6tp256qq9kac5/wokovoxi.pdf In PDF document text
    • http://aucoindeshalles.com/menu/file/77556977864.pdfIn PDF document text
    • http://maciejabramowicz.pl/upload/files/file/53705952773.pdfIn PDF document text
    • http://dioceseofniranam.org/userfiles/file/86579472042.pdfIn PDF document text
    • https://www.mppoa.cloudlinesystems.com/assets/ckfinder/userfiles/files/turefezim.pdfIn PDF document text
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608fe3cd13d60---51174368924.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/1612b8f8f972c2---33098918979.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/b7365ef8fc2729cda0744389be71ba62/kerudoniluwi.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609df6c803566---demonoturiromisevewap.pdfIn PDF document text
    • https://www.winsum.frl/ckfinder/userfiles/files/lukufip.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/rs98mctlcrq6v678sj1ejo8r5a/95489946394.pdfIn PDF document text
    • https://eijo.in/ckfinder/userfiles/files/78371164937.pdfIn PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/1f4a4b8fb92d958c3c753ef09ece2767/babimofumu.pdfIn PDF document text
    • http://aptwash.com/userData/ebizro_board/file/65596783219.pdfIn PDF document text
    • https://kaptenhoki.info/contents//files/mifaf.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/1e23fa69a97eb0a89f5bf16ab8519578/zakebegogimavedufe.pdfIn PDF document text
    • https://peintures-descours.fr/fichier/files/mumulewotokuviwele.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607081aa5dff8---68972343489.pdfIn PDF document text
    • https://www.cpro.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16072aa6989754---jikejukanefelotixeruwofuf.pdfIn PDF document text
    • http://studiorinaldibedin.eu/userfiles/files/netir.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160940544dd6eb---wagujusufuzumexonofimagu.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/cb1eb3fba49a939c6cacb8c880ac040b/75464533494.pdfIn PDF document text
    • https://sieuthimayphat.com/ckfinder/userfiles/files/vabejidajo.pdfIn PDF document text
    • http://cathugo-catamarans.de/res/wysiwyg/file/22155867651.pdfIn PDF document text
    • http://schoonhovensvrouwenkoor.nl/ckfinder/userfiles/files/jolujapiwakosamubofe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=exemple+de+bordereau+d%27envoi+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_off0000b516.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB516 14844 bytes
SHA-256: bbc86439f0b1d1816a3deb5ace30b18f717ab7a827056cae6e3ceeb205f00972
font_01_sfnt_off0000d95b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD95B 10816 bytes
SHA-256: e7b5158deecc255e131276a10013f8176a62bd937303619c1ef98ef874ef66c5
font_02_sfnt_off0000f208.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF208 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1