Malicious PDF — malware analysis report

Static analysis result for SHA-256 587fc1eb8ab8b4e9…

MALICIOUS

PDF

78.0 KB Created: 2021-03-20 13:54:15 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 36c8ec2deffeb66119be1446a131b2ba SHA-1: 588eeada3e7a5f03d9fe0aa7e69a9e3eeb1a8f10 SHA-256: 587fc1eb8ab8b4e9fcb9b004c444cef85c6bf65a4e0183d2d8262624af9c539d
126 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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.
  • 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://baarspo.ru/strik?utm_term=dark+souls+2+scholar+of+the+first+sin+dlc+on+disc PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4383921/normal_5fcf490785140.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4416302/normal_5fc9c0e674f7e.pdfIn PDF document text
    • http://palitra-cveta.ru/etymology_of_communication_meaning6b2mg.pdfIn PDF document text
    • http://arbitestpark.xyz/20285950240bvi9u.pdfIn PDF document text
    • http://vsspb.ru/guzikeg46ti.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4451753/normal_5fe13e8e8616c.pdfIn PDF document text
    • http://smartycredit.info/rival_crock_pot_manual_settingsiirvn.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421627/normal_601219e327d62.pdfIn PDF document text
    • http://verifiedbadge-lnstagram.com/cambridge_igcse_mathematics975kv.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://247e77cc-5367-4382-8586-7c5891409f42.filesusr.com/ugd/2dbf5a_22520a65c98d452886f2e2d5d398255e.pdf?index=trueIn PDF document text
    • https://4eb83289-b313-4542-b68c-79a1d4783db4.filesusr.com/ugd/f6336d_21439ffb2e454afe97610283bf634386.pdf?index=trueIn PDF document text
    • https://1c019786-7048-4615-837a-ae53f087c4ae.filesusr.com/ugd/8b4172_5012bb5c282849769bba4a06513c6239.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/mejigavukolu/vosumalul.pdfIn PDF document text
    • https://4ab51db4-2ab9-4ce7-8cf9-a7235cd4f8a6.filesusr.com/ugd/c6359c_a224560cf1144e82bd36f7d1da8e5e44.pdf?index=trueIn PDF document text
    • https://e9b66cc5-9289-431c-8f17-6739e1cd2d88.filesusr.com/ugd/c8f33b_d54ac044ed774b63857b704bcaa2e38f.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/jirebonudur/fedegewiginewinuxibinati.pdfIn PDF document text
    • https://35548484-ce42-4b18-9d9d-834326683263.filesusr.com/ugd/a221b6_6320690994e3491b91a7d61b5b1d64b2.pdf?index=trueIn PDF document text
    • https://167c8e7b-8160-49a2-a88e-f26749d647c8.filesusr.com/ugd/1ad47d_09ac1fcc62604b168a9422c18af8a2f3.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/wunupalezozerud/99086638441.pdfIn PDF document text
    • https://s3.amazonaws.com/subopukomanaw/fractions_equal_to_1_2_worksheet.pdfIn PDF document text
    • https://s3.amazonaws.com/tajimipojimo/he-_aac_sample_file.pdfIn PDF document text
    • https://f85e9a30-dbb9-40fd-a66d-53bd7daafe07.filesusr.com/ugd/1b9faa_a137657459e24d62a09ae9952799d8b2.pdf?index=trueIn PDF document text
    • https://9e0ebcba-7e04-41ac-afc6-cfc574163c15.filesusr.com/ugd/6725b5_d0c6e15e9fdc444782439807565ab08e.pdf?index=trueIn PDF document text
    • https://de99c131-68bf-4271-bcef-cda292486844.filesusr.com/ugd/f5892c_665984c8a23942688a326915fd5e0462.pdf?index=trueIn 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_off0000eed0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEED0 5304 bytes
SHA-256: 7708938afbc95077f7af300f4595ee879f2c73a2e3c3fae4088c918facd91e49
font_01_sfnt_off000100de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100DE 11616 bytes
SHA-256: 593d291a498eb5d4a291d3681b1fdd2b55d91dd01aed79ee9ded3315bc1a3092