Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a3027f588749312…

MALICIOUS

PDF

79.8 KB Created: 2021-06-09 21:58:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 41fc3e6250804801b7f17ef5d8125936 SHA-1: c74dbbcd2b45c8b8e05f9dd542aa401d667a4708 SHA-256: 1a3027f588749312ce76108f25d008719929484ef37a5c21187159e89a5a68e8
186 Risk Score

Malware Insights

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

The PDF file was identified as malicious by multiple heuristics and an ML classifier, with ClamAV detecting it as Pdf.Phishing.Trojan. The file contains a large number of external links, many pointing to disposable hosting services, suggesting a link farm or phishing operation. The presence of embedded URLs and the nature of the heuristics indicate an attempt to redirect users to malicious sites, potentially for credential harvesting or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://coretry.ru/pbw?utm_term=frida+movie+streaming PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4457620/normal_5ff188d8d7cf8.pdfIn PDF document text
    • https://xisaxori.weebly.com/uploads/1/3/5/3/135324705/xivusarivuwi.pdfIn PDF document text
    • https://kobuvedubi.weebly.com/uploads/1/3/4/0/134017802/3776629.pdfIn PDF document text
    • https://tijozamuworibop.weebly.com/uploads/1/3/1/6/131607374/6272739.pdfIn PDF document text
    • https://sazulolako.weebly.com/uploads/1/3/1/4/131453808/gibisegumafari.pdfIn PDF document text
    • https://tebuzemuba.weebly.com/uploads/1/3/4/0/134042716/4827f067a6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459481/normal_6063699c96937.pdfIn PDF document text
    • https://felelitujafi.weebly.com/uploads/1/3/5/3/135392562/fixutujisarelama.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/15c1c81d-6771-4e5b-8798-7cbcd4f08081/all_you_need_to_know_about_the_music_business_audiobook_free.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6aa5c5b9-67ca-42c3-b057-283845130f59/las_medias_rojas_emilia_pardo_bazn.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8e6d2269-b205-4251-af19-d5b0dc72ba4f/miwiguzofagijib.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/291c4f46-6c5b-4b5d-bee2-d2234e3d99e7/zebra_gk420d_label_software.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d5d121ae-a358-478b-ae48-02c02da6e824/11286106738.pdfIn PDF document text
    • http://dirujodela.pbworks.com/w/file/fetch/144904521/50884380564.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bb38bd3b-370d-455f-9527-f543926655f1/98808132853.pdfIn PDF document text
    • http://gijutexamuwa.pbworks.com/w/file/fetch/144873756/how_to_sew_stretch_fabric_with_singer_machine.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_off0000fc0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC0B 5128 bytes
SHA-256: 477df1f274d337b14d271f00474a938c789e83227c61a8774289d4b2ce89ec26
font_01_sfnt_off00010d6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D6F 10932 bytes
SHA-256: db7e114b4efafd0298e47ed0866b2d895a3f68dbb8dd45a35854600d9456ac2b