Malicious PDF — malware analysis report

Static analysis result for SHA-256 490929652caf01c0…

MALICIOUS

PDF

70.5 KB Created: 2021-03-22 18:37:06 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: 3b4316c67b4ea14627e8be7c77aaa299 SHA-1: 59e422d9edad19cfac2e82c59322a3a2f3f8d469 SHA-256: 490929652caf01c0de15442a5160770c5569c198c1618ef6e5aff4698edb7fcf
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The primary URL, https://midufefew.ru/award?keyword=physiology+pdf+ak+jain, is likely the initial lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://midufefew.ru/award?keyword=physiology+pdf+ak+jain PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4366047/normal_60240a5c24248.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474977/normal_605821ae0a9d4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453747/normal_6045e67c92071.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4487186/normal_5fee6685d143b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4479446/normal_5fe78bdc856ea.pdfIn PDF document text
    • https://cdn.sqhk.co/legexere/pifqFjf/16214872750.pdfIn PDF document text
    • https://cdn.sqhk.co/vovewotutal/ifhiSdC/88529145452.pdfIn PDF document text
    • https://cdn.sqhk.co/ravawiku/Uwvgjic/lazer_spot_inc_savannah_ga.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://85377554-d84f-42a6-a955-c87f7d5d3d8c.filesusr.com/ugd/dd4472_39e3b97da55b47f684a1700408f057fc.pdf?index=trueIn PDF document text
    • https://7f06b679-e14d-4525-8955-d56a7cf6f710.filesusr.com/ugd/79e5df_3cb34f64af224b0e8109ac02d46e9676.pdf?index=trueIn PDF document text
    • https://d934ed86-632c-4751-b35b-4303166f997e.filesusr.com/ugd/be0f55_3a3f452ce9864d96999f57ea00cf3a41.pdf?index=trueIn PDF document text
    • https://88966db1-4a83-4446-b941-f65022a6235f.filesusr.com/ugd/928e0f_052fa8b9cc4641cf9e36ba811a972834.pdf?index=trueIn PDF document text
    • https://709e7e89-b264-4d73-b757-064736ed86f1.filesusr.com/ugd/f523c3_130baf9284a546838b0bd8d9196126a4.pdf?index=trueIn PDF document text
    • https://cb6d8354-940b-4e05-9f1d-0150973ab277.filesusr.com/ugd/882da0_60683957afec411890c69e50d2f8b459.pdf?index=trueIn PDF document text
    • https://cef8af8d-7071-4339-ac50-fc417d371010.filesusr.com/ugd/a89196_4658ffe0a18f411dac41af4b4f7fd13d.pdf?index=trueIn PDF document text
    • https://f07eb630-23ff-4298-a1df-d7940f1ba2dc.filesusr.com/ugd/097a5b_5e364a8ec5bc46a2b0c10c6d76a71701.pdf?index=trueIn PDF document text
    • https://492f55f4-3442-4b37-b17e-39d9f2f0ae8a.filesusr.com/ugd/7dfe85_aec36b7dc021450ab825c82994894877.pdf?index=trueIn PDF document text
    • https://df867d32-629d-4b48-af14-2fc5df20f827.filesusr.com/ugd/287761_ef21269fd3544fb18ca0e1fa3b51249d.pdf?index=trueIn PDF document text
    • http://dijilupejiba.rf.gd/wuzuvomobobobe.pdfIn PDF document text
    • https://f3874c2d-c116-49c2-b7b6-9300dc8fc43e.filesusr.com/ugd/b11f6d_bd54bb51c7304760b2bef95f04d2485b.pdf?index=trueIn PDF document text
    • https://246406bc-bb0d-4f29-baed-d8a6153a9543.filesusr.com/ugd/3ddeef_029fa16058844ca1950d3370024323ca.pdf?index=trueIn PDF document text
    • http://bogadigoxizalux.epizy.com/30271139420.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_off0000d499.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD499 5448 bytes
SHA-256: 6bfc4f06d49df5121c311901dbb85f3187646e4989aead9ccd3dddb19910a359
font_01_sfnt_off0000e73c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE73C 11184 bytes
SHA-256: d7f71da607fefbd486ec3f1ec135d6847e245b0f0af5c766872ce9d45b659148