Malicious PDF — malware analysis report

Static analysis result for SHA-256 f85a0d435dd77018…

MALICIOUS

PDF

67.3 KB Created: 2020-11-28 15:56:06 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 387464b6bd12bf7678c289fbac5d56dd SHA-1: dcb1abac044e657431c14be3d3f055fd7d1c1e2c SHA-256: f85a0d435dd77018cc3510614dc7dfd5a534605e5c691ffe60d021f0f7773318
156 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 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://trafficel.ru/123?utm_term=funciones+exponenciales+y+logaritmicas+ejemplos PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4456398/normal_5fad60900b0ac.pdfIn PDF document text
    • https://timelasabo.weebly.com/uploads/1/3/4/3/134345700/c6048be9ad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378383/normal_5f8b8ee507460.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/wupiwupiwot/tripwire_lee_child.pdfIn PDF document text
    • https://s3.amazonaws.com/genedonapubefe/peaceful_piano_music_sheet.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b35d30cb-fa0c-4c65-a1de-eb11bfad40f1/daily_language_review_grade_2.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b75b996f-c3fb-4f90-b80d-2379bfff45ec/linobejasemevasopafipivo.pdfIn PDF document text
    • https://s3.amazonaws.com/kavitokolezub/pemojo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ed64ce69-363a-4da4-a429-8e247f02703c/schindler_s_list_worksheet_movie.pdfIn PDF document text
    • https://s3.amazonaws.com/gotenukevepunin/65811598401.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_off0000c432.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC432 5452 bytes
SHA-256: cfbea16ccb721bdc54dd97348ebfa2334c38df8f1c7f52a2d2316fecd1c03a6a
font_01_sfnt_off0000d6c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6C7 12160 bytes
SHA-256: 7f122f0957c004276cf6ee6b3e02276ce38728d9d6cf5ac889d55d70c6ace027