Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a34610322801c72…

MALICIOUS

PDF

78.3 KB Created: 2021-09-13 06:12:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 78faebdb83e757e0093ae4982e7bace5 SHA-1: 0b9d6b32b32f631845722593bd8bbd8917a7154c SHA-256: 7a34610322801c72fe25c852eb1007ce3ff8ac0907e29fca0185c768b4da1dcc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous embedded URLs that point to compromised WordPress uploads and disposable hosting, suggesting it functions as a link farm. The presence of these links indicates an attempt to redirect users to potentially malicious sites, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure and URL patterns are strongly indicative of malicious intent.

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://medvor.ru/uplcv?utm_term=basic+stereochemistry+of+organic+molecules+by+subrata+sengupta+pdf PDF link annotation
    • https://www.ksmt.edu.np/assets/ckfinder/userfiles/files/kikoxalif.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613913c1e4853---13436649125.pdfIn PDF document text
    • https://equator-maritime.com/userfiles/file/namokofikapixizinud.pdfIn PDF document text
    • http://tuanlongland.com/upload/files/losanudafilu.pdfIn PDF document text
    • https://lawyerupsmart.com/tempimg/file/24183927872.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/161362e1e4b54f---3401399052.pdfIn PDF document text
    • http://htk2.altrodesign.eu/ckfinder/userfiles/files/93327896700.pdfIn PDF document text
    • http://lifecare4all.com/upload/files/36631148628.pdfIn PDF document text
    • http://mygotour.com/FileData/ckfinder/files/20210906_DCE7F45EFC5C3C47.pdfIn PDF document text
    • http://sooam.com/files/fckeditor/file/8770700216132f89f0664b.pdfIn PDF document text
    • http://gazdalkodjokosan.hu/img/userfiles/file/47274482571.pdfIn PDF document text
    • http://www.chp.pl/ckfinder/userfiles/files/42997824822.pdfIn PDF document text
    • https://pmcp-avac.com/files/upload-ckfinder/files/kixamexisezebuz.pdfIn PDF document text
    • https://champion-osk.pl/userfiles/file/89418270521.pdfIn PDF document text
    • https://soechi.com/userfiles/file/zolavajetimonuxamotamaram.pdfIn PDF document text
    • https://cs-nippon-cp.com/mailmagazine/upload/files/livusawatomo.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130be1793ca2---tafaxezonodag.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ededbc43f3---47436463786.pdfIn PDF document text
    • https://gobelsprofil.com/upload/files/verapijuwesa.pdfIn PDF document text
    • https://fceresources.com/ckfinder/userfiles/files/32909334941.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_off0000c94c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC94C 11476 bytes
SHA-256: ef28197a3a4e162a00594a6505de823bdb6b33fc336bb3dc0670629221659d64
font_01_sfnt_off0000e3dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3DD 17776 bytes
SHA-256: b02a66aa2db9ed050c14256df19e6163e563a33ae2a89d88ae06d6218ffd2a0c
font_02_sfnt_off0001129d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1129D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1