Malicious PDF — malware analysis report

Static analysis result for SHA-256 acb5d8aa2f6f76c8…

MALICIOUS

PDF

73.3 KB Created: 2021-09-02 23:53:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 542b5ef8640579a0a742f62897e7fb29 SHA-1: f0dbccaa1ccd9f397024a14bcd94217e8c323d83 SHA-256: acb5d8aa2f6f76c89b73143b147500bb7795acaf1b89807459244b69e77dcd81
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm or phishing lure. The document body is unreadable, but the presence of these link farms strongly indicates an attempt to redirect users to malicious or deceptive content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/2grvpnj7bjmcj023vmssgv7h60/9352816271.pdf In PDF document text
    • http://skisun.it/userfiles/files/21908980366.pdfIn PDF document text
    • http://kameleonhastanc.hu/files/file/61488522963.pdfIn PDF document text
    • https://amblamy.ee/upload/file/7232177322.pdfIn PDF document text
    • http://tikatalog.sk/_files/file/bupijaferezonekariximi.pdfIn PDF document text
    • http://royalgoodviewresort.com/Uploads/file/12143061671.pdfIn PDF document text
    • http://ilpeace.org/assets/ckfinder/core/connector/php/uploads/files/5657482610.pdfIn PDF document text
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/2f8078832008cee64cbd8119215d87e8/matobejedu.pdfIn PDF document text
    • http://tamker.hu/userfiles/file/9632612093.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/160770f401b3ff---zamezututonipemevowapora.pdfIn PDF document text
    • https://bcm.es/files/galeria/files/dofujoba.pdfIn PDF document text
    • http://gearonlaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wepomiminajewu.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6bdf823be0---mivugolidodek.pdfIn PDF document text
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/00bcrh9lq8imdu9kn5h51fsp95/zujudasasezaluwojuvi.pdfIn PDF document text
    • http://www.toeterloeh44.de/files/10746592606.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606c90aa6b853---romujufivev.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1607b1a4f50577---kazetev.pdfIn PDF document text
    • http://cintabogor.com/Uploads/userfiles/files/33868314481.pdfIn PDF document text
    • http://seksdagen.nl/userfiles/file/tomutowasarojadopiruzibe.pdfIn PDF document text
    • http://cerezolorente.com/files/cerezolorente/_repo/file/nesavudidagabon.pdfIn PDF document text
    • https://voolabs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac127d4755a---jusovenur.pdfIn PDF document text
    • https://oklogistic.lv/upload/file/17410757816.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=animal+husbandry+terminology+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_off0000bbdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBDD 16632 bytes
SHA-256: a3bc64f081514d46c5672d0f6fcc035d915fc9d9719477a937f83be9506346d9
font_01_sfnt_off0000e617.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE617 11280 bytes
SHA-256: 4e9fb4cb54e0be9523cdf96bf554fb44d198d48c17dff017b110a5340d67a46d
font_02_sfnt_off0000fff3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFF3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1