Malicious PDF — malware analysis report

Static analysis result for SHA-256 41e4426f86169b90…

MALICIOUS

PDF

81.1 KB Created: 2021-09-19 01:45:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 61fc0c37de6d68663db2e4570650e95f SHA-1: 5c2f6e292f74b686e82b9d2c35887406264c2ed1 SHA-256: 41e4426f86169b90730156c4f528e7ed5f1471a3fb996682a745c6a3debc8494
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to various domains, many of which are hosted on compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware. The document body is unreadable, but the heuristic firings and URL analysis confirm a link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/161318bd544a57---51662586873.pdf In PDF document text
    • http://joinsocialbubble.com/cake/beta/userfiles/file/wusiditilujapim.pdfIn PDF document text
    • http://aloeverajuice.cz/files/file/8548528947.pdfIn PDF document text
    • https://xtremefitness.com.au/application/third_party/ckfinder/userfiles/files/xavewoxojajebujanaz.pdfIn PDF document text
    • https://netiko.ge/img/Data/file/vevomorikel.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ed38f3e56a---28033840871.pdfIn PDF document text
    • http://usmleworkout.com/files/file/65838165594.pdfIn PDF document text
    • https://mtestbd.com/assets/uploads/files/49073217935.pdfIn PDF document text
    • https://ptogel1.com/contents/files/97315841780.pdfIn PDF document text
    • https://advantage.ee/media/contents/file/xafikofumuwadu.pdfIn PDF document text
    • https://hanyauntuktesting.com/contents/files/61119277291.pdfIn PDF document text
    • https://istanbularicilikfestivali.com/upload/ckfinder/files/temuzigisimofolapi.pdfIn PDF document text
    • http://suarezbeltran.com/aym_images/files/bukapexaxarikekifubef.pdfIn PDF document text
    • http://hoteldazegliotorino.com/userfiles/files/89024303299.pdfIn PDF document text
    • http://orthodoxnews.us/file/bufewovepovanigunur.pdfIn PDF document text
    • http://elcolono.net/userfiles/files/63635429714.pdfIn PDF document text
    • http://mudrberanova.cz/userfiles/file/1435522537.pdfIn PDF document text
    • http://villaelen.it/userfiles/files/dixesomilalivo.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145761a72cf6---punajinazaxekebut.pdfIn PDF document text
    • https://propertiproperty.com/Uploads/userfiles/files/88923736830.pdfIn PDF document text
    • https://webrobogo.hu/kepek/20829290237.pdfIn PDF document text
    • http://himalayakebab.irafbrothers.com/shipinc/userfiles/files/85974748946.pdfIn PDF document text
    • http://thumpamonpally.com/userfiles/file/guloribuj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=samsung+galaxy+ace+4+user+manualPDF 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_off0000d878.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD878 17628 bytes
SHA-256: 979b86280c01ad6f23796afc22fe4ac9c568a726ff1560492d4892516226aa0c
font_01_sfnt_off000105e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105E8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011dff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DFF 10732 bytes
SHA-256: 2b49af4747d70b393628b00a605aac0045b28c7c9205f89a4b8346f321725906