Malicious PDF — malware analysis report

Static analysis result for SHA-256 812920bc1cebac7a…

MALICIOUS

PDF

80.6 KB Created: 2021-06-05 13:07:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 917e68f498c31e1c07cbd2d80fd48f77 SHA-1: 6a5f5af4f363286230da5849818b830edb0a2b63 SHA-256: 812920bc1cebac7ad820c8eba86c81612ece1d786cbcd7b7577e160024a3aa10
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which are hosted on disposable domains or link farms, indicating a malicious intent to redirect users. The ClamAV detection and ML classifier strongly suggest this is a phishing or malicious content delivery mechanism. While no scripts were explicitly extracted, the PDF structure and numerous embedded URLs point towards a tactic of redirecting users to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://drafthe.ru/pbw?utm_term=plantilla+de+escritura+para+imprimir+pdf PDF link annotation
    • https://lefagetali.weebly.com/uploads/1/3/2/3/132302894/1731604.pdfIn PDF document text
    • https://tirilume.weebly.com/uploads/1/3/4/8/134886795/tabanu.pdfIn PDF document text
    • https://rapugudunoxe.weebly.com/uploads/1/3/4/0/134012743/364693a1c95534c.pdfIn PDF document text
    • https://rukewopesix.weebly.com/uploads/1/3/4/2/134266340/9f64a22d8c9ba.pdfIn PDF document text
    • https://subogepaweb.weebly.com/uploads/1/3/2/3/132302814/vuworebujofa-tiwiv-turunijesapoz-kukiroke.pdfIn PDF document text
    • https://watuxiso.weebly.com/uploads/1/3/2/7/132740831/lupinopo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://wefolevemud.pbworks.com/f/jofuwibejiwufewet.pdfIn PDF document text
    • http://magobok.pbworks.com/f/88277851186.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d7dcde8e-db70-4681-919f-2c7fb76da5a7/27615544074.pdfIn PDF document text
    • http://foziwedugumu.pbworks.com/f/52442099706.pdfIn PDF document text
    • http://zedilowozare.pbworks.com/f/97279535122.pdfIn PDF document text
    • http://mogulazedub.pbworks.com/f/pixotoser.pdfIn PDF document text
    • http://wepoline.pbworks.com/w/file/fetch/144450807/how_long_do_you_look_at_the_amsler_grid.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7d7f2e18-0483-4f00-afbd-893239b0ef85/93761658542.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/84a407e2-025d-4296-b396-935ea4a9f475/woolworths_job_application_forms_printable.pdfIn PDF document text
    • http://fixunomavow.pbworks.com/f/lupabazamezamadunero.pdfIn PDF document text
    • http://savavaze.pbworks.com/w/file/fetch/144569205/graco_pro_x7_manual.pdfIn PDF document text
    • http://lakebimutep.pbworks.com/f/92457652540.pdfIn PDF document text
    • http://finatin.pbworks.com/f/exo_travel_the_world_season_2_sub_espaol_ep_50.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e4c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4C7 5300 bytes
SHA-256: c40092f178d2cbcc66c031c5a2b839fa4d38244c18a066e969359bb7e84dd0bb
font_01_sfnt_off0000f6bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6BD 11940 bytes
SHA-256: 6af2082a6ef46d38a20478cbe816ea78c802b4abe35fd3510e1a244fec145399
font_02_sfnt_off00011d5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D5F 16312 bytes
SHA-256: 975089639afea594160f6daa1ae948ffc4125994d61a9fd32dce02580f7b6b15