Malicious PDF — malware analysis report

Static analysis result for SHA-256 a63cd844892dbc64…

MALICIOUS

PDF

78.6 KB Created: 2021-03-27 13:55:12 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: af97fe548dcd3436e5ebaa00bef03cba SHA-1: 554ef10665ab7deb12ba47d8b228340a2c8f8bf7 SHA-256: a63cd844892dbc64ba37ebd6c77c17ea8857ffe572ef5884ab059b25affe57cc
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous external links, many pointing to disposable hosting, and exhibits characteristics of a link farm. The presence of a 'download' button lure and the ML classifier's high confidence score, along with ClamAV detection as 'Pdf.Phishing.Trojan', strongly suggest malicious intent. The primary goal appears to be SEO manipulation or directing users to malicious content via a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://leonvi.ru/award?keyword=wilcox+s+surgical+anatomy+of+the+heart+pdf+download PDF link annotation
    • https://vidufatow.weebly.com/uploads/1/3/1/4/131438098/siluribisonorejofus.pdfIn PDF document text
    • http://neojust.ru/whatsapp_riddles_with_answers_in_telugujko1p.pdfIn PDF document text
    • http://gexomafe.mypressonline.com/57092582015.pdfIn PDF document text
    • https://tulelamesesixe.weebly.com/uploads/1/3/5/3/135321102/mepotidibez.pdfIn PDF document text
    • http://buloshnaya.site/wwii_pub_quiz_questions0cajh.pdfIn PDF document text
    • https://feposejixadolo.weebly.com/uploads/1/3/4/7/134744373/9b7a29066d39.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/c563757f-14fc-44f9-bafe-16404ccc024b/29902127755.pdfIn PDF document text
    • http://pikaderobiw.atwebpages.com/79357406967.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b4bf289f-f8b5-4cad-a191-2d2960aa79b1/97181752283.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5ca37e21-17c7-41bd-b1b8-2b5e09ca3f49/the_end_of_eva_explained.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1edfa36f-30f3-4aa4-bff9-3175f6f4b791/pakizijitusu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/613a807f-b4ad-40d3-9e58-191d5f6f345b/how_often_to_do_knee_strengthening_exercises.pdfIn PDF document text
    • https://s3.amazonaws.com/diwitapezu/hp_laserjet_1020_plus_printer_drivers_for_windows_7_32_bit.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/17d7c7af-daed-4fee-9434-52cb11779d65/where_the_wild_things_are_costume_ideas.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9735fad2-505e-4e60-b566-44973fd42ab1/hero4_silver_4k.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3092aff1-1965-4a88-a25c-2ea487d745d2/14417787756.pdfIn PDF document text
    • https://s3.amazonaws.com/jemazejodep/pokapulivezovawuxirivev.pdfIn PDF document text
    • https://s3.amazonaws.com/voxipanovigepiv/sony_xplod_woofer_1000w_price_in_pakistan.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8100d498-d73a-4273-83ae-3777f577fff5/what_does_restrictions_a_mean_on_a_texas_drivers_license.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_off0000f33e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF33E 5844 bytes
SHA-256: 74282038b48965b925ed63d871648b672021024538145ef5e66d8a5a5ffe78a9
font_01_sfnt_off00010721.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10721 10492 bytes
SHA-256: 17ae07b641d4a238048d7e15f5156c6321594eb8b384e641e9bbfe1bbb5090e5