Malicious PDF — malware analysis report

Static analysis result for SHA-256 36e88e2d81370c50…

MALICIOUS

PDF

77.8 KB Created: 2021-09-03 09:56:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 0b372f353372557237596c8ece3d0413 SHA-1: 15b268c0330e87e028358c25b82a7fb80e4555ba SHA-256: 36e88e2d81370c503db178c9d43e255a7762d484c473d77f71065659609cfc67
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by both ML classification and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to numerous external URLs, several of which are hosted on compromised or disposable domains. This pattern is commonly used for phishing or to distribute further malware.

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://newtech-utm.pl/userfiles/file/80914590762.pdf In PDF document text
    • http://ks4073.com/file_media/file_image/file/87030106637.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610634f01a3db---boxujab.pdfIn PDF document text
    • http://ahoba85.com/clients/2/26/26d353b61ac95a99d7df5001a3d58300/File/63609477121.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/gu6fan62gkir2qcvkqc4rkeosi/66556064627.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d2d5796599---sosixojireziwuli.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/xadafumivizerovam.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/a315f45a8951cc4a7af9260089a02e96/46104095348.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7c4454dd0e---32778650463.pdfIn PDF document text
    • http://marleenjansen.nl/images/uploadfiles/xapepobinine.pdfIn PDF document text
    • http://armanetti.com/images/pogogurejovu.pdfIn PDF document text
    • http://graficaeformazione.it/userfiles/file/91263724961.pdfIn PDF document text
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/hmmnefq0eu7ss587v4hekf4gb0/risogi.pdfIn PDF document text
    • https://sporyolu.com/resimler/files/bajinunovemozimokexuzo.pdfIn PDF document text
    • https://topclassgreenery.nl/images/file/bapesalamexubul.pdfIn PDF document text
    • http://mixmarketing.vn/upload/fck/file/88652169054.pdfIn PDF document text
    • https://classconnbio.com/img-jacson/files/50460075586.pdfIn PDF document text
    • https://circolodelpistone.ch/userfiles/file/kesuxobuwazilisukirojewa.pdfIn PDF document text
    • http://bdn10.cz/files/file/89866029449.pdfIn PDF document text
    • https://am-system.eu/ckfinder/userfiles/files/depasoganujunelatuxij.pdfIn PDF document text
    • http://identik.hu/editor_up/70045623408.pdfIn PDF document text
    • http://aaaexpressheating.com/userfiles/file/97065971678.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=squares+till+50+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_off0000cc66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC66 10844 bytes
SHA-256: 85c62b762fbe563a83d26abba61ac9f6113c89bb1f38ed4a15d0088140cfe834
font_01_sfnt_off0000e560.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE560 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fd72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD72 17216 bytes
SHA-256: 0b71c5e7c3261e19b86232fdb94d1b6f13d123ab933dd63fa9f4b4543bdefd31