Malicious PDF — malware analysis report

Static analysis result for SHA-256 539c88f9495375aa…

MALICIOUS

PDF

73.6 KB Created: 2021-06-09 05:34:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 9d17b4276e64eb8a4ce74fbad736eac8 SHA-1: 69b8cbe2ffd21287475d497c9a1559dd1db487b1 SHA-256: 539c88f9495375aa6c03547fc7773fa4c3fe6464cb7e348b7f90b9e4ffefad0d
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to Weebly-hosted PDFs, suggesting a link farm or phishing campaign. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically identified as a phishing trojan. The document body, though heavily obfuscated, contains a URL related to 'hacked monster legends apk', reinforcing the phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://huntic.ru/pbw?utm_term=hacked+monster+legends+apk
    • https://bumekutuwa.weebly.com/uploads/1/3/1/4/131452846/xamimasirijuzafi.pdf
    • https://dekupepevimozis.weebly.com/uploads/1/3/0/7/130738652/baloxa.pdf
    • https://toxisejaris.weebly.com/uploads/1/3/4/8/134851702/8833805.pdf
    • https://boxagotogod.weebly.com/uploads/1/3/4/4/134491964/b3bf2e.pdf
    • https://cdn-cms.f-static.net/uploads/4454808/normal_6067e12265724.pdf
    • https://cdn-cms.f-static.net/uploads/4380539/normal_605fb478c951c.pdf
    • https://static.s123-cdn-static.com/uploads/4486060/normal_5fed7ccb588e1.pdf
    • https://cdn-cms.f-static.net/uploads/4375702/normal_60651d44e2a0e.pdf
    • https://static.s123-cdn-static.com/uploads/4465709/normal_5fcc541020f10.pdf
    • https://wirolarem.weebly.com/uploads/1/3/1/6/131636642/681841.pdf
    • https://cdn-cms.f-static.net/uploads/4501980/normal_6024a210b817f.pdf
    • https://static.s123-cdn-static.com/uploads/4480155/normal_5feb0d44eb51f.pdf
    • https://cdn-cms.f-static.net/uploads/4389384/normal_5fd2ffffc7cbb.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/bab09663-2698-4751-960f-adaec908a7de/how_big_should_a_2_year_olds_vocabulary_be.pdf
    • https://uploads.strikinglycdn.com/files/8188d808-b6c5-46c9-82f8-ff02cc8c3588/how_to_gain_weight_in_7_days_naturally.pdf
    • https://uploads.strikinglycdn.com/files/1409d498-ef8e-4314-bb2c-2fa211067c11/tipos_de_sistemas_de_informacin_gerencial_ejemplos.pdf
    • https://uploads.strikinglycdn.com/files/385a3e7f-c3e8-472f-8e46-c8e8c18c99b5/air_force_1_black_friday_sale_2020.pdf
    • https://uploads.strikinglycdn.com/files/473ca9f9-fddb-4fd6-a200-c7c64980bb53/economic_skills_lab_table_talk_interpreting_data_answers.pdf
    • https://uploads.strikinglycdn.com/files/616fa9d2-cee9-46cd-84fa-16f71ba38acd/when_to_change_transmission_fluid_honda_pilot_2012.pdf
    • https://uploads.strikinglycdn.com/files/2025da46-ac8e-449d-b262-a9425ab3fe04/citizen_two_tone_eco_drive_ladies_watch.pdf
    • https://uploads.strikinglycdn.com/files/c44bada2-ec39-41bc-aa10-8f6c2404d68a/43525944439.pdf
    • https://uploads.strikinglycdn.com/files/7b5d09ef-fd77-4b9b-94dc-692d41df9016/one_of_us_is_lying_characters_names.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e33c.bin
5e8a888c01c705f5f9542ab838ec0d3c558c7a26495c1e77a0d12504a9ace109
pdf-font-stream PDF embedded font (sfnt) at offset 0xE33C 5420 bytes
font_01_sfnt_off0000f58e.bin
5277d687ff5386f06b57db17e8d22045f986f15d8572bd2d6b40837727e2d229
pdf-font-stream PDF embedded font (sfnt) at offset 0xF58E 10480 bytes