Malicious PDF — malware analysis report

Static analysis result for SHA-256 31cbd9271a428dd1…

MALICIOUS

PDF

67.9 KB Created: 2021-06-07 04:51:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: cd7ba3db2fe9ffac317a1c159a2cdc20 SHA-1: d60594614774e0c06b5930ab200c54e525f1e44d SHA-256: 31cbd9271a428dd10478eb7be1a74f3a68f4dddc4b8d78026cfa652f73fdfde8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous external links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to lead users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://allytemp.ru/uplcv?utm_term=face+laceration+repair+cpt+code PDF link annotation
    • http://casier-a-bouteilles.com/file/parizolikoruzusuxokebun.pdfIn PDF document text
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/f226ed5b844a2f501190a62fb63845a3/34860230768.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/iqq4ljq7tb7oi2jpmi76618gke/10279879096.pdfIn PDF document text
    • https://www.reachcast.ca/wp-content/plugins/super-forms/uploads/php/files/33847afb6b15f13d3f9c330663f44420/dosomugisitevonuv.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bb8e3122d4---59314677332.pdfIn PDF document text
    • https://al-farh-iq.com/upload/userfiles/file/27719261336.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aeaf3f9d62c---32135023263.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/xojaluvawalerivisa.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/a7882b68895fd2e93d7451ca35f4f8ed/9372428784.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160aa129ad47f3---binifejadax.pdfIn PDF document text
    • https://dbjadow.pl/attachments/file/kofemukotaxo.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/09193bc30f626d0e1e6b85226187d147/zoxudazitefixamalop.pdfIn PDF document text
    • http://aqbnb.com/uploadfile/file/72551672222.pdfIn PDF document text
    • https://roweryelectra.pl/app/webroot/uploads/file/1621537925715.pdfIn PDF document text
    • http://alsumiri.net/wp-content/plugins/super-forms/uploads/php/files/ae409ae92df2a9a002ea8a177f049c68/lemelawamidirotuwagupog.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/1417871723.pdfIn PDF document text
    • https://kompaspt1.com/contents//files/ledexokozufisolimeburi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d01d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD01D 4844 bytes
SHA-256: 52fe9e2cc2350ebda6e0ef16ea4e077a4efbc9fe79d04dc95863d47e0024fd7a
font_01_sfnt_off0000e0a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0A4 9856 bytes
SHA-256: 89c2c15274f9ff7721e9bd8a2e41338850269eabe561425691eee6278632887d