Malicious PDF — malware analysis report

Static analysis result for SHA-256 4aacfa23936ab7bf…

MALICIOUS

PDF

81.6 KB Created: 2021-05-09 00:51:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: d99f5405bc83c787d19c378cf63b4630 SHA-1: 50f0229fdeeb6ff77948ae7bfafabd0d6d6c8b2e SHA-256: 4aacfa23936ab7bf14b40246b3769ca835ebf93124e162e5bee420e519c9d604
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://bologen.ru/strik?utm_term=how+to+take+a+motorcycle+permit+test+online PDF link annotation
    • https://sufifova.weebly.com/uploads/1/3/4/7/134736026/152fc584.pdfIn PDF document text
    • https://sowupetu.weebly.com/uploads/1/3/0/7/130739285/d7a8dc10ab.pdfIn PDF document text
    • https://kiwewogulexir.weebly.com/uploads/1/3/4/3/134307720/pikojotogo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4496389/normal_6029acdd111ec.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4481695/normal_5fe55f18678ab.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368218/normal_605aeccca0170.pdfIn PDF document text
    • http://garisemow.22web.org/jasagifupokelenubaxafozur.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460682/normal_6022f725f12b4.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://relipig.epizy.com/percy_jackson_2.pdfIn PDF document text
    • https://1cf095b7-1d29-4152-b82c-7733cf7ba0c7.filesusr.com/ugd/c1de29_0a8d2a653b1743c89031c8561e96e6f8.pdf?index=trueIn PDF document text
    • http://bosurigazo.epizy.com/rexovuvozakigenogabeg.pdfIn PDF document text
    • http://wepinipinalojud.epizy.com/4627654046.pdfIn PDF document text
    • https://58eafb2e-ea74-4523-a1b2-d2e0fe9bfe54.filesusr.com/ugd/466fa0_591f4b0f796149eab0957268d6331713.pdf?index=trueIn PDF document text
    • https://56148a0a-83a3-4003-94ff-78d3044b7c00.filesusr.com/ugd/6f5f23_d15b35fa4e0448f0bdf586997e2a4120.pdf?index=trueIn PDF document text
    • https://ff06b2c9-6223-4357-b4d5-1bf3807c749f.filesusr.com/ugd/717131_82dbbdd8686149a7a72d95db186ac43a.pdf?index=trueIn PDF document text
    • https://48e5b1ff-25fb-49a4-826b-3ad3f3a15688.filesusr.com/ugd/0d632a_8ad4d8ab3c134bae9dcc4d878b184bf0.pdf?index=trueIn PDF document text
    • https://318abaa7-a496-4882-a5ef-186b1d719b20.filesusr.com/ugd/ff2e65_8b3a9771a08649e999d16af1a5a5f058.pdf?index=trueIn PDF document text
    • http://toloruware.rf.gd/brinell_hardness_chart.pdfIn PDF document text
    • https://bdc3fad0-85dd-4e34-85f7-620d54d4ff6f.filesusr.com/ugd/10cedf_effd9f5bb96846158c7217dd322d6c8b.pdf?index=trueIn PDF document text
    • https://f74ea38a-ab8d-49a0-8d31-9a1d7ce64423.filesusr.com/ugd/5ceade_ed1f82309d9240b9bead3c6cc7fe64a1.pdf?index=trueIn PDF document text
    • https://bcd7deca-fd5d-492b-a220-d373ca515bc9.filesusr.com/ugd/12f4eb_83b69cb74322487fade7d7878806a329.pdf?index=trueIn 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f374.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF374 5088 bytes
SHA-256: 2815f86568042e9c5e45455fea74b8b053b3195f3c468ac5af42def830ca6b27
font_01_sfnt_off000104b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104B7 11200 bytes
SHA-256: 7a9c54cd263648943dccf5c27642495311efefd0c02fe53478772a52ff420078
font_02_sfnt_off00012aad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AAD 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333