Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c13e3acbc4e21da…

MALICIOUS

PDF

80.3 KB Created: 2021-03-27 17:03:23 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 179d467add9a751f3ac18f8bd77ff4e0 SHA-1: e3c4ec2df3a236cc2bfd11ea5cb08f515ae1a5e4 SHA-256: 5c13e3acbc4e21da12a3dff34c5e709fe1d254f0ea62f076422000cafd8aaae7
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to disposable hosting services, indicating a link farm or SEO manipulation tactic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or hosting malicious content. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • 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-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kuzutuzo.ru/award?keyword=los+comuneros+german+arciniegas+pdf
    • https://cdn-cms.f-static.net/uploads/4375075/normal_6013b8223f8d6.pdf
    • https://cdn-cms.f-static.net/uploads/4475565/normal_602a152bc050a.pdf
    • http://fiziwafofekaku.mygamesonline.org/conejo_abelardo_castillo.pdf
    • http://natosabi.mygamesonline.org/76808246141.pdf
    • https://static.s123-cdn-static.com/uploads/4484804/normal_5fdccd1ee98d7.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://ee6bc897-aa08-459d-b6e6-b1b1d69fcba1.filesusr.com/ugd/7ba596_76fa3b0fd3bf44c8bb954c38f2390807.pdf?index=true
    • http://kofaxafogi.myartsonline.com/broom_2020_effective_public_relations.pdf
    • https://d5f1d3db-1598-48d0-a061-764c190a6564.filesusr.com/ugd/866690_c5ef3acb9fe745009fbb316a467822ea.pdf?index=true
    • https://e301b21f-f707-426c-a094-6199d4b1a2d6.filesusr.com/ugd/f65518_fa7e96c279e846a39f3f470cf1ccbdb8.pdf?index=true
    • https://983c8978-ad56-435f-a988-47358aa6040c.filesusr.com/ugd/06a663_14b6d6bd2437427185942ba6ccf11001.pdf?index=true
    • https://8b8c7005-3af0-45a1-8e5b-a6902caa9335.filesusr.com/ugd/dbd7d9_c06463f27c5d4b2a887647c46d57c7b0.pdf?index=true
    • https://c78267de-509c-4cb0-9394-6b21b7876e04.filesusr.com/ugd/290ce3_7e77c9bd0c5c48c3b98273399823b974.pdf?index=true
    • https://9170d309-caca-4186-8987-bf6b40ce219c.filesusr.com/ugd/baef12_0237bbb20805481ea26d796ac9c6c928.pdf?index=true
    • https://uploads.strikinglycdn.com/files/c5a35106-e7bb-4255-8e6f-f4b477398a9f/32270552352.pdf
    • https://uploads.strikinglycdn.com/files/91aceb53-5210-4dfc-9081-4395ed97d3a3/fisher__paykel_refrigerator_problems.pdf
    • https://2fe0a9f4-4d23-48c4-8711-d5fb25093877.filesusr.com/ugd/683a75_5225b302abd74731b62b286d965e4b9c.pdf?index=true
    • http://kepofif.onlinewebshop.net/sizabipim.pdf
    • http://piwolimosopobu.myartsonline.com/pileladamabikopulogo.pdf
    • https://uploads.strikinglycdn.com/files/057b22f8-d505-4dc6-a58b-076299382f78/pabogitiligezobugifajesip.pdf
    • https://s3.amazonaws.com/fumiposamisur/touch_of_heaven_hillsong_piano_sheet.pdf
    • https://3e80c8bf-0031-4ca1-bfa9-4484641fefed.filesusr.com/ugd/08103e_63704b052498465fba929d09f408607d.pdf?index=true
    • https://uploads.strikinglycdn.com/files/c676cea2-b5c3-497a-a8bb-e4b1dcb220b0/tascam_dr-05_stereo_portable_digital_audio_recorder.pdf
    • https://s3.amazonaws.com/kumasala/compare_plugin_for_notepad_v7._5._6.pdf
    • https://s3.amazonaws.com/votawawo/renton_reporter_obits.pdf
    • https://s3.amazonaws.com/rivazixexuguri/ziwazunosunuwam.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_off0000f833.bin
19d49669c31354c9d3a8e418d6a546f1466a6992df4064f41efb55d5f972bed1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF833 5384 bytes
font_01_sfnt_off00010a72.bin
641417aa1935e29c2cf90b9261dab01e29a034ed8a82ba4dac8468b464ce0812
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A72 12524 bytes