Malicious PDF — malware analysis report

Static analysis result for SHA-256 6bcfc690b7bc73bc…

MALICIOUS

PDF

75.8 KB Created: 2021-03-16 07:39:59 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-04
MD5: 1fd944c37dd6b489d1a5d3d369d768e9 SHA-1: 38df2c87522fb1cde36a88d6f390177929bd0609 SHA-256: 6bcfc690b7bc73bcefad424111238778e550882031c23f1f9ac39e1518b8fac5
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to disposable hosting, indicating a link farm designed for SEO manipulation or phishing. The ClamAV detection and ML classifier strongly suggest malicious intent. The primary URL appears to be a lure related to 'bibliographic research', likely to entice clicks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://fokemale.ru/award?keyword=o+que+%25C3%25A9+pesquisa+bibliografica+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4373520/normal_600de78976d1b.pdfIn PDF document text
    • https://deremufirig.weebly.com/uploads/1/3/4/8/134854029/zuroledutid.pdfIn PDF document text
    • http://kismykeitio.best/fovuxejimewoc0o.pdfIn PDF document text
    • https://cdn.sqhk.co/fitamorigob/bThd2hh/godus_wars_gameplay.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369907/normal_601b767cbbebd.pdfIn PDF document text
    • http://winoraama.fun/gofewulosesodof2zvj.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4457862/normal_5fed3519663c4.pdfIn PDF document text
    • https://cdn.sqhk.co/ruvonusebex/iM4Osji/vijuwezoliwopoxumevip.pdfIn PDF document text
    • https://cdn.sqhk.co/befozaxulot/jahcjcV/mirakavukitoxufutufep.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449424/normal_5fe7ff902aded.pdfIn PDF document text
    • https://zuwuloju.weebly.com/uploads/1/3/2/6/132681456/776b42bc9c8400.pdfIn PDF document text
    • https://marezovunit.weebly.com/uploads/1/3/4/7/134719427/1459938.pdfIn PDF document text
    • http://snegny.com/fine_art_cv_templatetumui.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368984/normal_6046f6bd42a70.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://23c735dd-cbab-4b34-b334-20576347ef0e.filesusr.com/ugd/237bf7_13f84e098fa94451b1f4158f00645bf9.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/legipalofi/update_android_galaxy_s7_edge.pdfIn PDF document text
    • https://s3.amazonaws.com/dobikasukavu/64787732491.pdfIn PDF document text
    • https://99442e0c-e188-470f-b1e9-a2082f9e7f28.filesusr.com/ugd/2274a7_219a34fcdb0b4a3f9b4fcacfb498ec9e.pdf?index=trueIn PDF document text
    • https://78fa80b2-8629-447b-ad63-53e91e8d4948.filesusr.com/ugd/8f02de_4eceebe88fe94b699044a20484c940d3.pdf?index=trueIn PDF document text
    • https://29474179-7c7c-44ae-84e0-3c37792f2e25.filesusr.com/ugd/7f817d_a66df9e4736740289873a9d7079d6ee0.pdf?index=trueIn PDF document text
    • https://f3c4034a-4a94-4c47-b6c5-0445626d7bf8.filesusr.com/ugd/655f09_191a0730c77d46b7a7dfdf83db44e285.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e680.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE680 5760 bytes
SHA-256: 37bc3d627e754aa7d47fa18a09f7b768fbf8dd6382f9bb5ad0d86f933a28b177
font_01_sfnt_off0000f9d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9D0 12540 bytes
SHA-256: d5377cb62d764b09c026e7e21eecfecf6da3f0fd14c146b900df076b0a6f4b12