Malicious PDF — malware analysis report

Static analysis result for SHA-256 39c38975916bd8d2…

MALICIOUS

PDF

75.3 KB Created: 2021-06-01 08:35:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: da563cb92cf6d0a90d3de968acbe855f SHA-1: c5e11ffe44471939250476ff0a68b0753b348b95 SHA-256: 39c38975916bd8d229c8474b829795d4d1cc63038159e44385a3595e998fc8f4
126 Risk Score

Malware Insights

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

The PDF contains multiple embedded URLs, with a high concentration on disposable hosting services and link farms, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and a URL that appears to be a lure for subtitles, aligning with a phishing pretext.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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 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://allytemp.ru/pbw?utm_term=the+shape+of+water+subtitles+for+russian+dialogue PDF link annotation
    • https://kisumeselebo.weebly.com/uploads/1/3/6/0/136021012/9605217.pdfIn PDF document text
    • https://mulibini.weebly.com/uploads/1/3/4/8/134881685/bazepidebobuve_xididepa_rosig_puxesom.pdfIn PDF document text
    • https://zerevodajerut.weebly.com/uploads/1/3/4/5/134502997/jiwonaxevoti.pdfIn PDF document text
    • https://tuxufinuzeleki.weebly.com/uploads/1/3/4/7/134737217/lalabor.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490125/normal_6028112ebc0c2.pdfIn PDF document text
    • https://konatewed.weebly.com/uploads/1/3/4/6/134692195/9026466.pdfIn PDF document text
    • https://tafifomoku.weebly.com/uploads/1/3/1/8/131856516/rufusosewudelu.pdfIn PDF document text
    • https://mabaxezo.weebly.com/uploads/1/3/4/7/134766945/391b98faea7.pdfIn PDF document text
    • https://bumilumijoxaxuv.weebly.com/uploads/1/3/4/4/134497753/sitifixilirawiwufeji.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460981/normal_601298bd81ad3.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4384299/normal_5fceaf3749951.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/518ab8e1-576c-4776-a9e4-5e160b9bd0e0/rerupenomibanodejuzi.pdfIn PDF document text
    • http://letonepamusi.pbworks.com/w/file/fetch/144435297/how_many_chapters_are_in_diary_of_a_wimpy_kid_wrecking_ball.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/67b6add1-bf80-479f-8532-40cd573987ce/tipos_de_comunicacion_para_segundo_grado_de_primaria.pdfIn PDF document text
    • http://xojifot.pbworks.com/f/niwonazunubuvifuwemod.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5d8454cd-ef85-4352-836a-16ec5540bb62/elementary_korean_insun_lee.pdfIn PDF document text
    • http://nigezid.pbworks.com/f/engcon_ec219_for_sale.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/052d05c9-50f1-4bfd-8e7e-7e0f7f3da24b/partes_y_funcionamiento_de_un_motor_de_corriente_continua.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/63273f0a-48a7-4eee-b960-dd66db321b6c/probability_and_statistics_interview_questions_and_answers.pdfIn PDF document text
    • http://fevawigo.pbworks.com/w/file/fetch/144420981/56031541663.pdfIn PDF document text
    • http://zewalar.pbworks.com/f/34986745309.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fe667c45-9123-4889-bb75-0455040118f9/rugegaxagunewutogoda.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_off0000e927.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE927 5484 bytes
SHA-256: ec06ffd2a9fdaa826a774be0ebe0102fa1654db649f4cf0942ed4b679563b5ee
font_01_sfnt_off0000fbd3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBD3 10336 bytes
SHA-256: 48df1df623902b5dfe809149256a12e6a4515155a35b4403634128ffa8ec730e