Malicious PDF — malware analysis report

Static analysis result for SHA-256 43e3cb4e5babe3f3…

MALICIOUS

PDF

74.4 KB Created: 2021-04-02 12:32:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 49550bd46727e4f89bae96a2a2ae4338 SHA-1: ce564302dbce0929789fdcb9c066c11dd418526f SHA-256: 43e3cb4e5babe3f3f18a2e4380fe3a822c679cef8be9c41394417727d6bf2661
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable hosting and potentially malicious domains, indicating a link farm or SEO spamming operation. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The embedded URLs and the nature of the link farm suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://nipisod.ru/award?keyword=dental+articulator+pdf PDF link annotation
    • https://cdn.sqhk.co/zedugixaka/bihhaja/33511538325.pdfIn PDF document text
    • http://wetepuzasuvuroz.22web.org/7762796812.pdfIn PDF document text
    • https://cdn.sqhk.co/vefemenivu/conPgh3/75996622915.pdfIn PDF document text
    • https://cdn.sqhk.co/gukisafuw/GijOibg/19549737809.pdfIn PDF document text
    • https://cdn.sqhk.co/rivinodati/agRjaUF/lovecraft_country_book_plot_summary.pdfIn PDF document text
    • https://cdn.sqhk.co/gogojelawov/tgfjfig/face_mask_in_michigan.pdfIn PDF document text
    • https://cdn.sqhk.co/jetirivotu/Rgcogii/brimstone_haunt_psychosis.pdfIn PDF document text
    • https://cdn.sqhk.co/natokaze/Yctjia1/how_do_i_unlock_my_usaa_card.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/cefe080a-7808-4c08-9e3d-ecc9770d1e7d/kojekusorawisigomuwugigow.pdfIn PDF document text
    • https://d7d9470a-9784-4c28-ac68-b1ab0f70ddf3.filesusr.com/ugd/148484_360c8d89329c4686a32ae2fa86431e71.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/5d16bcdd-080a-469f-ba3d-360cb4e4051a/libro_de_sueos_borges_wikipedia.pdfIn PDF document text
    • https://43cb2d18-1589-43a7-b1c5-fe1278e1c76d.filesusr.com/ugd/370b54_4832e098085e4aa5805a5eee0f83def4.pdf?index=trueIn PDF document text
    • https://8dfd47f4-e591-4377-92a3-bdbf91d41e5a.filesusr.com/ugd/a58b01_581e2b25e6df4ead9444de68394ebece.pdf?index=trueIn PDF document text
    • https://e40da922-b0e4-44be-9878-2d4898ccab21.filesusr.com/ugd/3a38e0_867f10f8c9654eaf9e7e6062eabc330a.pdf?index=trueIn PDF document text
    • http://busixojap.epizy.com/algebra_with_pizzazz_answer_key_page_2.pdfIn PDF document text
    • http://kizifisen.rf.gd/nosuxurofasowezotunus.pdfIn PDF document text
    • https://cfae799c-d04a-4395-b2c2-700dffd2ed5c.filesusr.com/ugd/15504a_50ea2b40ee1b4640adfb105380834c5d.pdf?index=trueIn PDF document text
    • https://f4e740b0-69d0-4d5c-a0c7-362dc6b2ad6d.filesusr.com/ugd/0356fc_561123c68fa94d8b84bf2a2db81e068f.pdf?index=trueIn PDF document text
    • https://23da7c74-6e14-424a-b22a-901aa35eafb1.filesusr.com/ugd/9cc572_e59f78108f7b4f13973b3cb7b2793b91.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_off0000e1a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1A2 4968 bytes
SHA-256: 8f80e9b3c15c86fa249dc17e5372c1e34920f4896c45351fd335d8e15e43a90c
font_01_sfnt_off0000f2a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A4 12528 bytes
SHA-256: 4eef0d60e86e728f9f69f2974faa84ecea0db07ce84b2ce3bbab65a0f7f47742