Malicious PDF — malware analysis report

Static analysis result for SHA-256 5ac3fbb838734d9d…

MALICIOUS

PDF

92.7 KB Created: 2021-06-21 08:57:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: b0588dba8758b13f69f7145da0b0462e SHA-1: a1038817e24ae568b4015d8247231f3d6e381807 SHA-256: 5ac3fbb838734d9dd47217e37e01a41015ca3bf23897d8427fbddf56f0797ca8
196 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. It uses a password-protected-archive lure. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://stef-nancy.fr/upload/document/dufisodamurumu.pdf In PDF document text
    • http://jarosi.hu/files/file/nudapidaj.pdfIn PDF document text
    • http://hocikto.info/userfiles/file/86005313581.pdfIn PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091ec2825678---bawopagidigesuvuz.pdfIn PDF document text
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1608e72a36a5d7---resunamixoxiwilasomodi.pdfIn PDF document text
    • https://etadelloro.it/images/file/waxesumenewijinixozi.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/61aea926f28ce163efe803734d8e31bf/18907342668.pdfIn PDF document text
    • http://e-district.org/userfiles/file/57824722084.pdfIn PDF document text
    • http://albatrossmrn.com/konadnew/userfiles/file/21970178338.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c458a68562f---70608096264.pdfIn PDF document text
    • http://antifftech.com/uploadfile/file/%5C/2021061412593360.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a12bca230b9---fixajowasevorato.pdfIn PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/fe378d68d9288d5f04c6242710e3f60f/2026603940.pdfIn PDF document text
    • http://fedorahosted.org/lohitIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=free+kannada+novels+pdfPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off0000f49c.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0xF49C 36052 bytes
SHA-256: d39c7f6b96b0ad801f9433515aa69e74c918ed19a3ff8992de4b4d30d011b2e8
font_00_sfnt_off0000e31c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE31C 5112 bytes
SHA-256: 929f56dd437eaa690e75e9a7c8866744903e0f88876f90348c62a979844f0de3
font_02_sfnt_off000135ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135EA 2100 bytes
SHA-256: 9b8d1fadb692b7e2780bde0693a1b9f38854386d9b57de953eb94bff425be3a4
font_03_sfnt_off00013fc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13FC2 11056 bytes
SHA-256: ea4e18fb2009d3583653117fee14aba7a3a4ec92f1003bccbbf3193e0cd9be57