Malicious PDF — malware analysis report

Static analysis result for SHA-256 a759e29b2f5588a3…

MALICIOUS

PDF

80.2 KB Created: 2021-05-03 21:18:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: a2f4196dc1a508864514ee2f8514ed05 SHA-1: be10b2e8760a4d4a414d5776b08a4de1d239d1b8 SHA-256: a759e29b2f5588a321f4b8490f9b0213db8cad63cdf3309345af5dcac40ef761
226 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a fake browser/software-install lure. 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 0.9998

Heuristics 7

  • 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.
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://crophysi.ru/strik?utm_term=sql+guided+project+coursera PDF link annotation
    • https://cdn.sqhk.co/fefamuve/cxWssYh/ice_scream_horror_neighborhood_2.pdfIn PDF document text
    • https://cdn.sqhk.co/xenumobavun/rhaSZsz/slam_dunk_festival_2015_lineup.pdfIn PDF document text
    • https://cdn.sqhk.co/tuwagezo/RBOjz1P/balloon_rocket_experiment_worksheet.pdfIn PDF document text
    • https://romenazojojeles.weebly.com/uploads/1/3/0/7/130775884/gilimafilom.pdfIn PDF document text
    • https://cdn.sqhk.co/gekakisoduvo/jcjf4gc/37357001577.pdfIn PDF document text
    • http://moscowflowers.shop/sipaxaxawekimufefmog2.pdfIn PDF document text
    • https://cdn.sqhk.co/vipikunowi/gEhdjap/lucky_draw_bingo_game.pdfIn PDF document text
    • http://useraisins.pro/why_does_yeast_respire384wz.pdfIn PDF document text
    • https://tizevilujiv.weebly.com/uploads/1/3/1/4/131406709/bunojamotumoje_mudosozajune.pdfIn PDF document text
    • https://fasadosuz.weebly.com/uploads/1/3/4/0/134012998/zazaposadutel.pdfIn PDF document text
    • http://paganel.world/what_are_the_disadvantages_of_coal_powero9rzq.pdfIn PDF document text
    • https://cdn.sqhk.co/pofadugilip/idwuvgc/download_toca_life_after_school_mod_apk.pdfIn PDF document text
    • https://buwuxebukiz.weebly.com/uploads/1/3/1/6/131606134/kidobugefepaga.pdfIn PDF document text
    • https://nepufetok.weebly.com/uploads/1/3/1/4/131438640/numufupavi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://f7e05ffc-afae-4d19-be15-7e9c659e5e5f.filesusr.com/ugd/72f62b_96b34a8547c64afcb1090888a631f3af.pdf?index=trueIn PDF document text
    • https://e86c6366-0652-46cb-9e1f-5633a133dba9.filesusr.com/ugd/510a18_c91d69e7532342dea60320e9eb389f75.pdf?index=trueIn PDF document text
    • https://87098103-4d08-48bb-90a6-807b0ef734b2.filesusr.com/ugd/1f49de_ea24c04f257f43539b7dffe6331095f6.pdf?index=trueIn PDF document text
    • https://770ad53b-b55e-4e58-b1eb-3709f41304f7.filesusr.com/ugd/98e298_a6bee376d4c74fa3baeadb9267a0ef0b.pdf?index=trueIn PDF document text
    • https://9d03b195-5c34-4993-8a23-519dd2bddccd.filesusr.com/ugd/9ac058_b5f97866ebb5465f859e975a3462b2f9.pdf?index=trueIn PDF document text
    • https://ebba3e40-d49f-4cc8-b137-373bb1124918.filesusr.com/ugd/384ea4_bba91ea87cd042dcbd2d1faf7cdd1fa8.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000effe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFFE 5324 bytes
SHA-256: a4cdc89e50de140fb786028396ebda24faad58a78a9c8b44303282fd0da2df88
font_01_sfnt_off00010220.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10220 10676 bytes
SHA-256: d97d252176ed8f356a9a9ba559463aea00d151649ce69d887e5bbe7533145039
font_02_sfnt_off0001267c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1267C 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3