Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb5d9ffb91bad973…

MALICIOUS

PDF

67.6 KB Created: 2020-11-20 06:54:54 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 8570cbdc31c604d50a1f5f7b408122d2 SHA-1: 28cf13a7540a91e19b6fdc3549f94b2788b69eb8 SHA-256: cb5d9ffb91bad9732ae802007991a4d339a977eec095d50a420e5bdb920ac651
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, a common technique for link farms or phishing lures, as indicated by the PDF_SEO_LINK_FARM heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URIs point towards an attack pattern involving redirection to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • 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.
  • 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://trafffe.ru/123?utm_term=dash+cam+for+2016+camaro PDF link annotation
    • https://tozifurijusewo.weebly.com/uploads/1/3/4/8/134850353/f68b8d1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4373516/normal_5f894cfe82836.pdfIn PDF document text
    • https://bilewazivabo.weebly.com/uploads/1/3/2/8/132816117/a7987f824.pdfIn PDF document text
    • https://femulonatif.weebly.com/uploads/1/3/4/5/134501650/tixidexibupotun.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447258/normal_5fa2b3848dc2f.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/felasorarabipis/73453028482.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eda9e2ea-dd40-4fad-90e4-686e99bd5a6f/40384941796.pdfIn PDF document text
    • https://s3.amazonaws.com/jumedemimo/contest_of_champions_mastery_guide.pdfIn PDF document text
    • https://s3.amazonaws.com/punurum/bireti.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fb6a714f-2e80-40d5-9f8a-8649cc9995d6/nijorikuxotesusanefati.pdfIn PDF document text
    • https://s3.amazonaws.com/mukut/jurasavaziselo.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_off0000c71b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC71B 5568 bytes
SHA-256: 48b2a31e5921a0aedda03d36fab093475af4cf245b23b457aac7320da4632919
font_01_sfnt_off0000d9e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9E8 11920 bytes
SHA-256: 5c24f21a8d847168943fe5af34aebf3a0fe495708cec07bb88427604791f25c7