Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb9e6305905e5788…

MALICIOUS

PDF

87.7 KB Created: 2021-08-03 05:23:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: df77e1397f39d0de689d4cbb77a496d0 SHA-1: 168dc896d97cb9bd0d859e443645fa9d2fb52653 SHA-256: fb9e6305905e57885fd83a3d0cb576574c4b144891522b2be5884abf6368ec48
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress upload directories, suggesting an attempt to host and distribute malicious content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, indicating the use of disposable hosting for SEO-related link farming, likely to lure unsuspecting users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/9035635d80638750f91ac9d9f3dbf8fe/81411943128.pdf In PDF document text
    • http://cukiernia-waltar.pl/qcms/userfiles/file/tubupowaxidodegij.pdfIn PDF document text
    • http://rgn2u.com/userfiles/files/87552068308.pdfIn PDF document text
    • http://burattinojatek.hu/userfiles/file/linutidazabuxutaziv.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac1e1f73e0a---5180915259.pdfIn PDF document text
    • http://k-sta.kr/FileData/ckfinder/files/20210720_1DADB2CBEA962515.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160920743a0965---febim.pdfIn PDF document text
    • http://etpatatietpatata.com/userfiles/files/ruzixodabizeraxa.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/eumgsfj66tj1bv3msvfrsn4t27/13484733264.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b37d61972cf---78321058009.pdfIn PDF document text
    • http://studiosiciliani.eu/userfiles/files/94345706695.pdfIn PDF document text
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160da8bc1c9f8a---59127021498.pdfIn PDF document text
    • https://nutstudio.it/userfiles/file/tusizarewiluridaput.pdfIn PDF document text
    • https://www.hemoroidklinigi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d481a50b13---91515806069.pdfIn PDF document text
    • https://xanbiente.de/userfiles/file/54598730416.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f866e8402c---8030592846.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/5a7ca4ab3ac494e6e5055ac10194467e/fitunawokulugigidaguf.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076e91a5d69c---6222181251.pdfIn PDF document text
    • http://ms-beauty.com/ckfinder/userfiles/files/seradafasividazav.pdfIn PDF document text
    • https://marigabung.com/contents//files/najibepo.pdfIn PDF document text
    • http://kwiatmetal.pl/userfiles/file/10498859187.pdfIn PDF document text
    • https://rkdestate.com/userfiles/file/25147019922.pdfIn PDF document text
    • https://ises.ca/phpsites/vertical_living/uploads/file/kozadafigofix.pdfIn PDF document text
    • https://stvorki.ru/files/file/59873674949.pdfIn PDF document text
    • https://musikkursus.dk/userfiles/file/fusum.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=dibujos+a+lapiz+faciles+y+bonitos+de+animalesPDF 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_off0000ec2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC2A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010441.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10441 11224 bytes
SHA-256: 4a0d26b3a7c8e2b7e6c74f5858e3a2f5fb1e26fbd71d9e2ff1ba6a8ab06ed21f
font_02_sfnt_off00011e5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E5C 18988 bytes
SHA-256: dc460fe7fd38ea844181d10966aa1f62f1f0800817ece190c87799b2b02569e4