Malicious PDF — malware analysis report

Static analysis result for SHA-256 85926f62d03354ac…

MALICIOUS

PDF

71.7 KB Created: 2021-09-04 21:07:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1817ddc15478c5ee6a27baa6e2445127 SHA-1: b3070ef02b599cbedb604a975d08046080279d3e SHA-256: 85926f62d03354ac67c1cbaad42a941b0e248097996049d36f5729375f78d089
156 Risk Score

Malware Insights

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

The sample is a PDF file flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous external links, many pointing to compromised websites or disposable hosting, suggesting a link farm designed to redirect users. The primary function appears to be directing users to external URLs, likely for phishing or to download further malicious content.

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 https://oniceh.ru/uplcv?utm_term=ks3+maths+online+worksheets PDF link annotation
    • http://marcelponjee.nl/ponjeefiles/file/10194629555.pdfIn PDF document text
    • https://albizy.com/ckfinder/userfiles/files/69697901717.pdfIn PDF document text
    • http://metrocars.london/survey/userfiles/files/roxofevabofakir.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c341e50067---49681712243.pdfIn PDF document text
    • https://www.alignerco.ca/wp-content/plugins/super-forms/uploads/php/files/ea7c9e55374dcdab49ce6dca9d637fce/95019340994.pdfIn PDF document text
    • https://iiml-pgpsm.in/ckfinder/uploads/userfiles/files/bonurivefedajeb.pdfIn PDF document text
    • http://thegioidahoacuong.com/uploads/image/files/51260853581.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/dc66b0b9379487e047a66b19eda2d53a/zekifowopokekodi.pdfIn PDF document text
    • https://jodhpurtravels.com/nbloom/fckuploads/file/zajevavabonidukalubagafe.pdfIn PDF document text
    • http://wawabed.pl/uploads/userfiles/file/13132871677.pdfIn PDF document text
    • http://bbpcosmetics.com/admin/upFiles/2021-6/file/4911680379.pdfIn PDF document text
    • http://arslanemlak.come/file/66109252701.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/robubodezasefudo.pdfIn PDF document text
    • http://mdsalon.ru/img/lib/file/nolitorilijas.pdfIn PDF document text
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086b7a0f07d3---93165957766.pdfIn PDF document text
    • https://panegovernance.com/ourprojects/chowki/UserFiles/file/11103097901.pdfIn PDF document text
    • http://www.multigacos.com/admin/uploaded/fck/file/giwifotive.pdfIn PDF document text
    • https://oddluzanie.net/userfiles/file/wawaloxinowewu.pdfIn PDF document text
    • http://bezagsecurity.cz/userfiles/96645233716.pdfIn PDF document text
    • https://thaiwoodengames.com/files/upload/files/56587681287.pdfIn PDF document text
    • 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_off0000b86c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB86C 10712 bytes
SHA-256: c4f2c6dc4a4078ac14fec7b6c0f508cf8bec896418bcdc2a3de280490cbf9899
font_01_sfnt_off0000d0f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0F2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e904.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE904 15984 bytes
SHA-256: b5f3cc2b88414945a8e32e6c82e6d926b3e34f9f0435feac548389fe782636e8