Malicious PDF — malware analysis report

Static analysis result for SHA-256 527722b9bb593d61…

MALICIOUS

PDF

82.9 KB Created: 2021-05-11 09:35:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: c548c57cff22a05e9f94e3cefe78b339 SHA-1: 512282b535c2236a5f4a49d8eafe25c1c1370158 SHA-256: 527722b9bb593d6100c97a3d27bec1db203b615bb26d67f02b4c862a10f9bf14
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and 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 0.9996

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://xajibur.ru/strik?utm_term=how+to+read+an+ekg+strip+for+dummies PDF link annotation
    • http://vnds-super.space/2037982870r5wb.pdfIn PDF document text
    • http://svarka-aurora.online/11102257366wpjcl.pdfIn PDF document text
    • https://cdn.sqhk.co/gaxozamikoge/Ihejh6D/nowiketadexifomijuni.pdfIn PDF document text
    • http://prizyivnik.ru/hp_photosmart_eprint_wireless_driver_downloadjmgcy.pdfIn PDF document text
    • http://tacfitproducts.com/shot_clock_basketball_for_pckotoe.pdfIn PDF document text
    • http://vulgargirls.fun/jezifitidaxikenoburode0qza3.pdfIn PDF document text
    • https://cdn.sqhk.co/mejeteboxav/icHb8mS/tasty_planet_forever.pdfIn PDF document text
    • http://ig-support-service.com/590259342106lcki.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://d2ea4bfc-f92a-4379-acf2-d9b69981ddb7.filesusr.com/ugd/739437_cd16ed4516d54442b7c228dfcbe35c08.pdf?index=trueIn PDF document text
    • https://ede8a7a3-2377-4e09-926a-401222b31c25.filesusr.com/ugd/81c89d_9ea2b1207ef64956a3b8658440a2bbb8.pdf?index=trueIn PDF document text
    • https://7722bba5-72ad-4d15-a72d-9ce9fbdcf1b5.filesusr.com/ugd/772ad5_783bfa330a0241ecbde817e6906c4b52.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/b26bbcdc-26e9-4727-87e6-9b28fdaca1d0/51626233480.pdfIn PDF document text
    • https://e028ba52-6c86-493e-86b7-fecf7cd1c3eb.filesusr.com/ugd/bcb9fd_3b3712c085354676b2940f9304663c53.pdf?index=trueIn PDF document text
    • https://694dae7a-2033-4a59-8b06-91ff4eec0774.filesusr.com/ugd/e1d58f_0baa1048daaa40c18e09aa998ef2b952.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/1b4819a0-8909-4268-bf46-b1f01385e315/45121605492.pdfIn PDF document text
    • https://a7da3e60-63c8-46c1-a846-eab7df628ed2.filesusr.com/ugd/bba345_bc39439cc8e04e31a39627a0e3b22c0e.pdf?index=trueIn PDF document text
    • https://e216d865-ddc7-438b-99b2-64609380b1bb.filesusr.com/ugd/7ae8b3_3d89769717514933add00e0f31e92b31.pdf?index=trueIn PDF document text
    • https://979cd01f-16ea-4d2c-b189-234964c95597.filesusr.com/ugd/d4c4cf_7a7a98c5561f4079b023a9d1453d4d9f.pdf?index=trueIn PDF document text
    • https://9e2b3e3a-6a02-4d3b-8ba9-5acc01041672.filesusr.com/ugd/66c878_47fdf7307839470386eba623e4dbac74.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/aa682019-0c38-4d0a-abf7-8fa839a1f4a4/86658239724.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3a0c68a0-4f14-479f-9c73-8d47c4971dcd/sat_2_math_1_practice_test.pdfIn PDF document text
    • https://874c0fd6-92eb-497b-905f-dc7ca4d2e287.filesusr.com/ugd/5ca7d4_31af3eca7ada4518a032ebe3fcc22f73.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_off000104b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104B6 5448 bytes
SHA-256: 1c891c16d345ed14a36934f4fbe9f79f77af50bf64ddadb5729ecaab9a870673
font_01_sfnt_off0001173d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1173D 11348 bytes
SHA-256: da039aa92a0f68ee9bebd8462ba682a138370d3cee28c937673ea68de9425152