Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a6380e19bb3d487…

MALICIOUS

PDF

72.6 KB Created: 2021-05-25 09:49:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: bbae4ad0b5fd76a7ba9f1b52ba408dd5 SHA-1: 72a9fcc0154ff98444af3d0de5672e0240064ac8 SHA-256: 3a6380e19bb3d4876c598a56daadfc598b7336d8417952e1215eee68af73b334
214 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to S3 buckets and other cloud storage services, suggesting a link farm designed to distribute malicious content. One critical heuristic identified a link to known malicious redirector infrastructure. The document body, though heavily corrupted, contains text related to downloading a free book, which is a common lure for phishing and malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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 links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://dafemum.ru/strik?utm_term=descargar+3+veces+t%25C3%25BA+libro+gratis In PDF document text
    • https://cdn-cms.f-static.net/uploads/4426263/normal_5fdb6db361e43.pdfIn PDF document text
    • https://wamazuwo.weebly.com/uploads/1/3/1/3/131380988/6370743.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4389108/normal_606ca00f3dc77.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4377098/normal_5fc666c8c28ca.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415950/normal_6026eec33748a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4480876/normal_5fdea586e102f.pdfIn PDF document text
    • https://wobofosowipifir.weebly.com/uploads/1/3/0/7/130776138/nivitaj_vameveb.pdfIn PDF document text
    • https://lufojujerap.weebly.com/uploads/1/3/4/4/134481619/1252423.pdfIn PDF document text
    • https://xizuxikeg.weebly.com/uploads/1/3/0/7/130740292/xepofuzutenod.pdfIn PDF document text
    • https://zazalefofano.weebly.com/uploads/1/3/4/5/134578352/jifimot-lepovakiz-xutebotupakab.pdfIn PDF document text
    • https://wozepunelom.weebly.com/uploads/1/3/5/9/135993859/72ae384f239.pdfIn PDF document text
    • https://kitabenulo.weebly.com/uploads/1/3/0/9/130969432/1188101.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/zaxawetawupo/94400214323.pdfIn PDF document text
    • https://s3.amazonaws.com/jubiferekaka/vomiwobera.pdfIn PDF document text
    • https://s3.amazonaws.com/xamapebonijos/sinagasipalasuxexe.pdfIn PDF document text
    • https://s3.amazonaws.com/wifiduxezo/72456208174.pdfIn PDF document text
    • https://s3.amazonaws.com/mafavuzenoliki/61877313846.pdfIn PDF document text
    • https://s3.amazonaws.com/bubeto/17688859828.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5fba53a9-aca6-48b9-b262-ea514dfde771/how_much_salary_do_mechanical_engineers_get.pdfIn PDF document text
    • https://s3.amazonaws.com/fedojigudaj/lightweight_tripod_head_large_format_camera.pdfIn PDF document text
    • https://s3.amazonaws.com/xafaxotaful/fixopalobadavamotopivafe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b6071ff5-e0ee-4428-b1db-aff991dadeed/what_is_modified_curriculum.pdfIn 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_off0000dc5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC5E 5448 bytes
SHA-256: b80fec1968d2299a955cdfec32081af09e955a2c7c0075d4154b76b743481031
font_01_sfnt_off0000eed5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEED5 11028 bytes
SHA-256: f92394dc37c579f1236dc729150f9aa12239b070f71ff0539bc7fa8c1271a1aa