Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b326f669ab402df…

MALICIOUS

PDF

67.7 KB Created: 2021-03-17 04:53:03 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 9daa016f7820cc703f78578c88cf13e7 SHA-1: b5e918e4cc3257d75aa664a67d2df6a854b99466 SHA-256: 1b326f669ab402dff5c469eb3076c76fe57c2a4a05de935c5f084afe5efe0307
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO spam operation. The document body, though truncated, contains metadata related to 'wkhtmltopdf' and a search term 'amoeba sisters properties of water answer key', indicating a lure to educational content. The presence of PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics, along with ClamAV detection as Pdf.Phishing.Trojan, strongly suggests a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://gimoguvi.ru/123?utm_term=amoeba+sisters+properties+of+water+answer+key PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4403818/normal_6025e69e8b9e0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367310/normal_5fd6a63247319.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4482402/normal_5fcd33c8f3b1d.pdfIn PDF document text
    • https://cdn.sqhk.co/kitaparek/icLVVIX/jixetalopumupiziseriti.pdfIn PDF document text
    • https://cdn.sqhk.co/zoribakim/bjhejhe/30862412552.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369505/normal_60051ad83c0a7.pdfIn PDF document text
    • https://cdn.sqhk.co/mamabukalom/ifgijjm/sedekulebebivu.pdfIn PDF document text
    • https://cdn.sqhk.co/gasariba/jjgfOib/buzabupeporobonaweluvumus.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4403817/normal_5fecb1841a8d2.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://weferobiditikun.epizy.com/solving_absolute_value_inequalities_worksheet_with_answers.pdfIn PDF document text
    • https://fc060a1e-8c1d-4b7d-bafd-75f79d4c6355.filesusr.com/ugd/c0a468_13f03dd280fe42ebb7dbd6a899dd7963.pdf?index=trueIn PDF document text
    • https://1e16f6d7-285b-4488-bf07-d3e24ac90e20.filesusr.com/ugd/417718_73fc8d09f2004c9296cec40a9f602a1d.pdf?index=trueIn PDF document text
    • https://1237a3da-0b33-4890-9ba9-974507bf2590.filesusr.com/ugd/3e0cb9_616d4fcd0ea34cf89615a3d0e44d050e.pdf?index=trueIn PDF document text
    • http://popewap.epizy.com/saqa_application_form.pdfIn PDF document text
    • http://motagetezo.epizy.com/arithmetic_logic_unit_alu.pdfIn PDF document text
    • https://920f4c01-5fd6-4c40-8b27-b99972fecb60.filesusr.com/ugd/d63aaf_eebf22082c4d4fbc9edaa327045700a3.pdf?index=trueIn PDF document text
    • https://2c91b947-1dd8-401e-ae91-d595f2f75867.filesusr.com/ugd/0af078_e0edf0eb78ed42e0af7c12d37ea2de91.pdf?index=trueIn PDF document text
    • https://f238abdf-92e3-4651-90df-65b6e8a648d9.filesusr.com/ugd/99965f_80db38b5188f45fea6ad49b966996767.pdf?index=trueIn PDF document text
    • https://1cf095b7-1d29-4152-b82c-7733cf7ba0c7.filesusr.com/ugd/c1de29_3ecf748b47234d5797ec700a59385e97.pdf?index=trueIn PDF document text
    • https://c96d0889-97fb-4213-90a4-a08ae01970e6.filesusr.com/ugd/ed32f2_5e90c18c4deb40828c2e2cf2d007f612.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_off0000cb3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB3B 5404 bytes
SHA-256: 621d30eb9571aed2ddd81db93eace9b6def46f6fee8cf7d9165a31f6e35c0d2a
font_01_sfnt_off0000dd99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD99 10308 bytes
SHA-256: f8406d76f11730b310c39363eb20dd2f6606ad6386f0a20bf3c9b083ea87da11