Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1d21cd9325c782f…

MALICIOUS

PDF

75.7 KB Created: 2021-03-22 05:49:57 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: a441550f37cbcd1ea781bc7c4f54f41a SHA-1: 57d163a9e78b393f10610678eec1c2eb34ba439d SHA-256: b1d21cd9325c782f42db3d49fc04ca4cc3df5fdea1f7d3f232f8e6abf7d3f6f8
186 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. 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 0.9991

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://crophysi.ru/wix?keyword=multiplication+and+division+of+rational+numbers+worksheet+pdf PDF link annotation
    • http://bubble1.space/50136194369su0ek.pdfIn PDF document text
    • http://giftcard-sale.store/tanerin9yzg.pdfIn PDF document text
    • http://reduslimitalia.site/beyblade_burst_app_apk_hereqgi8h.pdfIn PDF document text
    • http://xsale.trade/lijekakekukegwbm4.pdfIn PDF document text
    • https://mirinojasuri.weebly.com/uploads/1/3/4/5/134588432/jedot.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380079/normal_6048cef06720b.pdfIn PDF document text
    • https://fesoviso.weebly.com/uploads/1/3/4/7/134710514/febelujigixufozatedo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485443/normal_5fd640ff9495c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412154/normal_6047aa0e15647.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4411501/normal_5fdfb3802edb7.pdfIn PDF document text
    • http://calipshatngaccs1.xyz/lexonidiremavutijitdp1ro.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://54957a25-093b-4cbd-a4f0-8eb5fea931f0.filesusr.com/ugd/8ba634_a265cb9ee5424836822e593f72adc37f.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/e11c40e1-a1e0-4695-8fa9-7bf3f0820b90/98665798652.pdfIn PDF document text
    • https://91313464-3f42-441e-b0e8-b27065d471ad.filesusr.com/ugd/ee9d3f_1872780da477455c82c6b29e6a9c60bc.pdf?index=trueIn PDF document text
    • https://e2604e0b-f95a-4acb-b53f-a7db3827b2a1.filesusr.com/ugd/225520_67d90b2cc6b743099607357ce6e892d1.pdf?index=trueIn PDF document text
    • https://22e365c6-0853-42e1-82f8-83473bf9c0bf.filesusr.com/ugd/217d68_9e012dc36f97405384c67f2dcfd16785.pdf?index=trueIn PDF document text
    • https://917ed8d3-8a9f-4c5c-a3ad-554e533308ad.filesusr.com/ugd/a4e402_4e92a3de15b14b8c8c5edd03cec034aa.pdf?index=trueIn PDF document text
    • https://56148a0a-83a3-4003-94ff-78d3044b7c00.filesusr.com/ugd/6f5f23_93b5f24d21bc453a9d1ab9697bc834e0.pdf?index=trueIn PDF document text
    • https://b2d1eea7-aef5-47fc-962c-88b5513ecafc.filesusr.com/ugd/3a57bc_c0d1fd99d7d6435583544ba49bd57ec2.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/b3b8f516-7c59-4e9b-9bce-0df11542c2fb/how_to_draw_easy_stuffed_animals.pdfIn PDF document text
    • https://e06e8306-d71e-4c92-aa1b-e8c52eeb44cb.filesusr.com/ugd/bc4951_d4c3f6d0b6364d61a1586e78dc05595b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/083d241f-3441-4f79-96b5-ec0ccc923cd9/the_other_side_of_heaven_2_fire_of_faith_streaming.pdfIn PDF document text
    • https://c9b0c9dc-51ad-46ec-84b2-dbc26df53712.filesusr.com/ugd/b6f588_71d09af765f14986a2f4b2e1ef0e7d8d.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/caccbc27-84ee-4ab6-bef7-31698ae56088/how_to_use_amazon_web_services_to_host_a_website.pdfIn 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_off0000e637.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE637 5756 bytes
SHA-256: facee34545469f7037d88a6859c115eec0b8a52d5105a495c1d3a06f765846bc
font_01_sfnt_off0000f9c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9C3 11352 bytes
SHA-256: b33c973ccfdb8841137dd7179593c6020c26c2bd26f0f6bb5ca2032fd80cf59e