Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ef5bc703b19303c…

MALICIOUS

PDF

80.7 KB Created: 2021-04-03 05:55:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 6077026507e01f2ae6b9864b97243cfe SHA-1: 1088eb93dd36da8242de957168c8d06ba283681a SHA-256: 4ef5bc703b19303c9299bf20a50ea27f18e1ccc9863f143998014cf2cce06520
194 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. It uses an invoice-themed 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 0.9997

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.
  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://bologen.ru/award?keyword=budget+and+budgetary+control+pdf+download PDF link annotation
    • http://socialwave.me/64330477804jl460.pdfIn PDF document text
    • http://silkhfig.bid/american_pie_reunion_movie_in_tamilhf488.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402503/normal_603b2c96587c7.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4366024/normal_5fe23747b7e3e.pdfIn PDF document text
    • http://doucheapp.xyz/nenobonagatemisovodasodijd3ff1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371267/normal_604cc99c55ba9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369768/normal_5fd9b1f13b1db.pdfIn PDF document text
    • http://afracheat5.xyz/gcse_maths_algebra_worksheets0farn.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4382406/normal_5fdcdde8316c5.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/b8b532d8-d210-4b0a-b2b6-af5b6d38dfba/48293494237.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/90026968-749d-4934-9998-8f9aaad71a7c/53720767579.pdfIn PDF document text
    • https://769966b8-4adc-437e-bba8-f198cf6e171b.filesusr.com/ugd/41a0b6_2a87f5c26ce348319008cb9718c21ffa.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/234bf939-bea4-4f57-838e-fb20193bb735/olympus_evolt_e_500_buy.pdfIn PDF document text
    • https://09ec9d85-9312-4337-94d0-b84080e05f2e.filesusr.com/ugd/ac0094_8518dba6c2324e4399539136001ef866.pdf?index=trueIn PDF document text
    • https://951e66c5-660f-4748-bfcc-a6cc0831133d.filesusr.com/ugd/4967bb_cad4f7f659984bd9b54b7c133cacc1b4.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/farowug/before_answering_your_question_meaning.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5779825a-d342-4bfb-a9d6-fdf746c198ac/experience_and_education.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/db51420b-f6f4-469f-902e-51ce3acb8381/63677375198.pdfIn PDF document text
    • https://ba85394b-11ac-4ca4-926b-74ca936c52e1.filesusr.com/ugd/5ccfc8_cfbabe213ba54c6fab11abe42305ba81.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/sajatesawodiji/32062687184.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4ead62af-8a1f-4f1f-82ba-9a6bba044d18/little_red_riding_hood_characters_fairy_tale.pdfIn PDF document text
    • https://66f9c2bc-82a6-463d-9ccd-9c94d3d8805e.filesusr.com/ugd/b361c6_5d2630b7123c44fd9a1748626faae8ab.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_off0000ffa5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFA5 5528 bytes
SHA-256: 68ede407d6466aa33879db06a662d7d9a5285fc263727912e5f067e22b83f1d1
font_01_sfnt_off0001129f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1129F 10236 bytes
SHA-256: d857fc6e38dc2afd142e4de511ea14cbd0e95547f833b9416647c88ab418c0f3