Malicious PDF — malware analysis report

Static analysis result for SHA-256 87c849edbc0757d8…

MALICIOUS

PDF

78.7 KB Created: 2021-03-18 07:06:06 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: f28e98ce9556c63d40c9304de059af07 SHA-1: a300c5bbd98198af1cb634b44b3f803c69c3c71d SHA-256: 87c849edbc0757d8bd532fbc35dd4f5268391747a17f63abe9e74a088f7f7901
244 Risk Score
Tags
free-cdn-ebook-manual-lure

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to disposable hosting or known redirectors, indicating a link farm designed to distribute malicious content. One critical heuristic identified a link to a known malicious redirector at 'https://yafferge.ru/123?utm_term=best+keystroke+logger+for+android', suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection further support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/123?utm_term=best+keystroke+logger+for+android In PDF document text
    • https://cdn.sqhk.co/sibonawumup/hhciihj/admin_dashboard_php_template_free.pdfIn PDF document text
    • https://cdn.sqhk.co/wesaduleb/hdoe5if/dafelitilupomizugu.pdfIn PDF document text
    • http://susekilimu.medianewsonline.com/anemia_en_nios_oms.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366027/normal_6041b5fa2d632.pdfIn PDF document text
    • https://cdn.sqhk.co/fenazijeguk/Viihgcj/real_cooking_games_for_adults.pdfIn PDF document text
    • https://cdn.sqhk.co/lemipetukaso/leFhhjv/86106003379.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422385/normal_6021984eedf5d.pdfIn PDF document text
    • https://cdn.sqhk.co/toliximozupa/hahigfF/cyber_security_analyst_interview_questions_and_answers.pdfIn PDF document text
    • http://tewatag.medianewsonline.com/37392173485.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4452624/normal_600582d367914.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://e8f98835-b194-42a5-b43f-fe2f29920dd6.filesusr.com/ugd/bf650e_f855d6301a81440cb3650e0b1f6df97c.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/3e955315-3223-44ce-8ce5-71721874215c/standard_catalog_of_world_coins_1801_a_1900.pdfIn PDF document text
    • https://b064d0e4-88d6-4b7e-8087-8ebf790fcba6.filesusr.com/ugd/ca32a8_1a76b2b5db6c49a9b58d9e67a6a18f36.pdf?index=trueIn PDF document text
    • https://6db1e9a2-4282-4636-8d41-de07325ad911.filesusr.com/ugd/d97b38_2596e2b27f27487eabfc3e123980e096.pdf?index=trueIn PDF document text
    • http://bitines.myartsonline.com/nejetififutunegofaraje.pdfIn PDF document text
    • https://5405d108-7f1e-482b-a10c-e06f62b7505d.filesusr.com/ugd/d941b1_9e68d49684a1434d91d9e38e7ccf7772.pdf?index=trueIn PDF document text
    • http://kipejefanowisu.atwebpages.com/pretty_good_vs_very_good.pdfIn PDF document text
    • https://db244590-af71-4c33-bd6e-2f8f55f31281.filesusr.com/ugd/fdab61_7488c2e4b3e2498a9937a46b27c4aad8.pdf?index=trueIn PDF document text
    • https://5a1138df-423b-4a5d-a7c7-36223740754e.filesusr.com/ugd/a72fa8_0caf9dd1c15e4264ad377346f5b323cd.pdf?index=trueIn PDF document text
    • https://4e4301d6-cc9a-4939-960a-6b497c1efea6.filesusr.com/ugd/d78803_c8d6096a8b3f4c92943823c40484f530.pdf?index=trueIn PDF document text
    • https://1eba3b37-3dce-45e8-aa15-e51a58efc0fe.filesusr.com/ugd/89e37c_c04dd0279a7a41f4a54ca572632953ee.pdf?index=trueIn PDF document text
    • https://dd67658a-cc17-4e1c-bca5-42bf299a485b.filesusr.com/ugd/07a440_48fb8e9e76be444bb7dd3e3761d13ce9.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/f6204518-1dd5-4b75-a5cd-ba0a3a513067/dizatibenesajul.pdfIn PDF document text
    • https://dc58184e-bbba-402a-8e08-a55d552c8f3f.filesusr.com/ugd/0ebc1f_11c9dbaa2bfa4d03a5c8e8f564b1c23b.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_off0000f53a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF53A 5288 bytes
SHA-256: d70a6bc3fefe4ab3a2af157901a5daebc038912b5f804d85630ce5d92dee3efd
font_01_sfnt_off00010758.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10758 11276 bytes
SHA-256: e8acf1df23f7111464e16680deb3f430822ce4767b5e7ca5f9c60722c9a97fe2

Open this report in the interactive analyzer, or submit your own file for analysis.