Malicious PDF — malware analysis report

Static analysis result for SHA-256 28f21f88ec305733…

MALICIOUS

PDF

86.9 KB Created: 2021-04-26 02:11:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: f00d933d1e9b5753a99105847b573ed2 SHA-1: e4cb71442936168c35bee446c4bfbb0b432aba1c SHA-256: 28f21f88ec305733b227daa4b2e693070116be60acee5ac4e40d1f8a5853fa00
186 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including ClamAV and an ML classifier, indicating a phishing or trojan-like behavior. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, contains a title related to genetic testing costs, likely a lure to encourage clicks on the embedded URLs.

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://resalured.ru/strik?utm_term=how+much+does+genetic+testing+cost+for+pregnancy PDF link annotation
    • https://cdn.sqhk.co/feguzuvubut/Eia0hf3/rusexa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387590/normal_5fe8136152bb7.pdfIn PDF document text
    • https://cdn.sqhk.co/migefareg/aliigcN/79773177765.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459337/normal_600e67db7a706.pdfIn PDF document text
    • https://cdn.sqhk.co/fuxilumevo/chhogem/70083132966.pdfIn PDF document text
    • http://8bitbeardsco.com/hedwig_s_theme_viola_sheet_music_free0qu3p.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380867/normal_600ce4f5224ea.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366623/normal_601fabcb341fc.pdfIn PDF document text
    • https://cdn.sqhk.co/zirevazul/hd2yygh/schoolgirl_ai_3d_multiplayer_sandbox_simulator.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4453889/normal_5fe0a7df96cff.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369330/normal_60471106934a3.pdfIn PDF document text
    • http://i-men.ru/nc_dmv_can_i_renew_my_license_onlineskw5u.pdfIn PDF document text
    • https://cdn.sqhk.co/felinavaw/hdhhjdT/toon_blast_cheats_no_survey.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4425484/normal_5fc71e1071305.pdfIn PDF document text
    • https://cdn.sqhk.co/mojupesonon/db2C0P5/asteroids_arcade1up_brickseek.pdfIn PDF document text
    • https://cdn.sqhk.co/kerikone/jiIihib/76447643954.pdfIn PDF document text
    • https://cdn.sqhk.co/metusoteliza/azjehjV/desaruxewede.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://eb72eaa1-ef55-40a3-a653-f6d21bccf295.filesusr.com/ugd/54913d_e79efe287ea243259ee5b39b9a43941c.pdf?index=trueIn PDF document text
    • https://73808e0e-d5df-4584-b63e-1552d949bc0c.filesusr.com/ugd/8d2ea6_5b8cb36432bc4e6b8708f86644929599.pdf?index=trueIn PDF document text
    • https://a1f0096d-76f5-425c-b826-5ccbd312c1bc.filesusr.com/ugd/8f8c07_62fc325e4b6f4087af41f0ec48477e88.pdf?index=trueIn PDF document text
    • https://9c33b4df-6f14-41ad-9e94-a3a23f7ed20d.filesusr.com/ugd/2a975f_8a5620e2cc7c45ca9aef5bd213906aa2.pdf?index=trueIn PDF document text
    • https://edb7bb8d-792a-4213-93ec-7f573d37cc74.filesusr.com/ugd/bfd504_597e52d193c041739162b8cd5a233c6e.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_off0001155e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1155E 5692 bytes
SHA-256: cc8fe14040137f5cc4b524d960f7c4b593766d6ca4cc901db76c662dfe70aa96
font_01_sfnt_off000128a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128A9 10344 bytes
SHA-256: 90bf6768882b1a12296104ad45a5dac2857a996fb8bf783f5798ac0537edb988