Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c9ea760c6c110fe…

MALICIOUS

PDF

79.3 KB Created: 2021-05-06 01:59:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: 76c59940acb8985443c1fd7c88e58b34 SHA-1: bc81ed7f60bc88c58275f64f895570c800169cba SHA-256: 4c9ea760c6c110feaf723f0e72fab8bdc5440518498083c80280749dc7795678
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by multiple heuristics and an ML classifier, specifically flagged as a phishing trojan. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm designed to redirect users to potentially malicious content. The document body, though heavily obfuscated, contains a lure related to 'free pencil drawing lessons', likely a pretext to encourage clicks on the embedded URLs.

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://maypoin.ru/strik?utm_term=free+pencil+drawing+lessons+for+beginners PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4413846/normal_5fcb10e6ee1b1.pdfIn PDF document text
    • http://fofolep.mywebcommunity.org/xavupenoxawuxenur.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387814/normal_60433b872779b.pdfIn PDF document text
    • https://wafiludelo.weebly.com/uploads/1/3/1/4/131437380/lazug.pdfIn PDF document text
    • http://lexamopelezun.mywebcommunity.org/kujodadalazo.pdfIn PDF document text
    • https://xizejaselaz.weebly.com/uploads/1/3/4/3/134357450/8c804b3730c400.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486742/normal_602c63b2e6b6a.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://d33b8dfc-9792-4d26-9d81-613d0bd32a71.filesusr.com/ugd/d34367_41a77d8e9faf4bcb9d6ff385bfe7d51e.pdf?index=trueIn PDF document text
    • http://wurebosuloxu.myartsonline.com/gemafidu.pdfIn PDF document text
    • https://ed36ca5d-e6e9-4caf-8bbb-3a8af5cfee16.filesusr.com/ugd/971556_f4dbdb2c9f4d47b791381d2034d8c2d6.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/nemafu/serebimuwubitepe.pdfIn PDF document text
    • https://4b4b92a8-4ac5-4030-97d5-af0917f8c077.filesusr.com/ugd/0251f0_a85f1440a221459bb2d06c200962ec92.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/jagux/41578693480.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8a338dee-d167-451a-8547-5f695a11e0c4/king_arthur_and_the_knights_of_the_round_table_movie_trailer.pdfIn PDF document text
    • https://1e16f6d7-285b-4488-bf07-d3e24ac90e20.filesusr.com/ugd/417718_906c680636ea47f1b322faf75bfd1535.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/89b74ee3-8854-4a0a-aa4a-f447cb89a36a/monster_as_an_adjective.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b09cfdef-61f5-4559-9f06-d8eee27b026e/speed_queen_tr7_dryer_reviews.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4498f808-86e3-46ec-8210-54fd87a833ed/rosemary_baby_streaming_italiano.pdfIn PDF document text
    • https://ef2e072a-e8a2-4438-804d-cc750be2e2f6.filesusr.com/ugd/6a22cb_02a4a08c1cca43ae8658ecd07aef0813.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/9dfcdb00-67a9-4fd2-be23-f63c3d74f5ff/garofiniripuzokus.pdfIn PDF document text
    • https://s3.amazonaws.com/bezutu/42423055683.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_off0000f8f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8F2 5508 bytes
SHA-256: a1211c25558cbc0524ebd6077891323f6bae441e07de1f6aab34440ca8208e1c
font_01_sfnt_off00010bcf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BCF 10632 bytes
SHA-256: e356a30d3d0f233ccbf2851d2a2ccbee17aac263e07f94f7ba1743c3d83ecbcf