Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9c56752a3ca7247…

MALICIOUS

PDF

78.6 KB Created: 2021-09-02 08:16:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: c2a0f3661145500ac6eb7b01851cfd2b SHA-1: 4cd3356494b7f9cded115656ccfadf8caab23eb8 SHA-256: a9c56752a3ca72478413329979688d66811983dfdf141b124061b69a73699709
156 Risk Score

Malware Insights

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

The PDF file contains numerous links, many of which point to websites hosted on compromised CMS platforms, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and URL analysis point to a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://amicalelaique-guyancourt.fr/ckfinder/userfiles/files/19925265201.pdf In PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076b595eabbd---tefelamugosebogositedi.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2a8034fc1a---gixududerisa.pdfIn PDF document text
    • https://dejavuruse.com/userfiles/file/jevirezuk.pdfIn PDF document text
    • https://casabresciani.it/uploads/file/66081318491.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160871c901d79e---nowefoj.pdfIn PDF document text
    • http://asupuro.com/user_data/image/file/56989244005.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d07dd93ca7---39918395168.pdfIn PDF document text
    • https://geneticapanama.com/userfiles/file/15685293975.pdfIn PDF document text
    • http://zaun-produzent.de/userfiles/file/44614635922.pdfIn PDF document text
    • https://designclarf.it/file/mewemerugurog.pdfIn PDF document text
    • http://adance0112.com/upfile/editor/file/sinuduvamewusapij.pdfIn PDF document text
    • http://messtores.ca/fck_user_files/file/puxujiwivexamagu.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078f0d8b1cb0---nowipofupawenesibolafex.pdfIn PDF document text
    • http://codemessaging.net/ckfinder/userfiles/files/1931162861.pdfIn PDF document text
    • https://hpx.com.ua/wp-content/plugins/super-forms/uploads/php/files/7d26f62d03af9985a389cfcbb53dce7c/38912142701.pdfIn PDF document text
    • http://densayhongngoai.com/uploads/userfiles/file/fupodinonowa.pdfIn PDF document text
    • http://itkaufmann.com/images/fckimages/file/64858535954.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af95f68252d---42359211417.pdfIn PDF document text
    • http://volamtuyetthe.com/userfiles/file/90406170407.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160ce0c086ff9e---96185641513.pdfIn PDF document text
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1608b08049b559---daximiparuvuke.pdfIn PDF document text
    • http://doverhighschoolhalloffame.com/clients/2/2d/2d76883e1086210ef8e2c43836b0327f/File/lutajadiwojak.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=free+radicals+and+antioxidantsPDF 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_off0000cfb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFB1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e7c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7C3 17404 bytes
SHA-256: b7038fd2997103b826aba7548aea1cab1fa540c7e379ff3ab5e253163678c4a3
font_02_sfnt_off00011490.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11490 10440 bytes
SHA-256: 726ee45024c33e4686f1959d9630e5ef812bed8c96e3d7a0ad2c21de42a125af