Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac3f86b319e6a682…

MALICIOUS

PDF

80.6 KB Created: 2021-03-07 17:22:18 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: faf4ac97b5318df91fd9c25a4a7dba97 SHA-1: 16e108985563948c089599fed8fb2227fb814a93 SHA-256: ac3f86b319e6a682c025eebc49f920f898abca1fa41a5b60f0b2e2d027acb8f9
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 hosted on disposable domains, suggesting a link farm or phishing campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded URLs and the heuristic 'PDF_SEO_LINK_FARM' point towards an attempt to redirect users to potentially malicious sites, possibly for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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/strik?utm_term=masterbuilt+oil+free+turkey+fryer+recipes PDF link annotation
    • https://fanawilixu.weebly.com/uploads/1/3/1/4/131408209/novituwojodanepava.pdfIn PDF document text
    • http://xegazinijitup.mywebcommunity.org/nintendo_error_code_50099.pdfIn PDF document text
    • https://lupawepenotude.weebly.com/uploads/1/3/1/6/131606523/debopujilimuza.pdfIn PDF document text
    • https://nuvusutapisi.weebly.com/uploads/1/3/4/4/134460305/vipolukifa-sezebaviropi-kozebul.pdfIn PDF document text
    • https://lefamadagizid.weebly.com/uploads/1/3/4/7/134704745/futunimorizitugiw.pdfIn PDF document text
    • http://fisujerekuvij.getenjoyment.net/against_interpretation_download.pdfIn PDF document text
    • https://bomejafir.weebly.com/uploads/1/3/4/7/134725936/fegekijizepe_xiramanefube_mebumizurori.pdfIn PDF document text
    • https://pusesame.weebly.com/uploads/1/3/4/6/134662227/3254290.pdfIn PDF document text
    • https://xonarupitowij.weebly.com/uploads/1/3/4/6/134617661/waxerab.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://77483064-5892-4b52-b419-66e751946b77.filesusr.com/ugd/ef7b09_1d36cef392c741e3a97980c969ad6bb6.pdf?index=trueIn PDF document text
    • https://45f0f727-c607-4398-b3b7-8b42e23b21b2.filesusr.com/ugd/0a84ca_c5fcbc5877a64a4fb4aa7da856af5807.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/182659a2-9f77-4787-ad3b-5afada4cc193/fewujoluresukixokipin.pdfIn PDF document text
    • https://ed4d48c2-14ea-47f5-a89a-b82193587323.filesusr.com/ugd/8ce377_f1afb72179794d76a17c17f1fe1565b0.pdf?index=trueIn PDF document text
    • http://bitujiduruv.myartsonline.com/canon_rebel_t5i_details.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c4d8c5fc-e5d9-4174-8179-91bbbd9801cd/zolasodawaxodazuzapa.pdfIn PDF document text
    • https://058da8ce-bb30-4b8c-81eb-8903018cac65.filesusr.com/ugd/ab745b_e7f1f2c004fc4553bf7969b34522671b.pdf?index=trueIn PDF document text
    • https://b3a1a1c9-4f8f-4fb8-b7cc-7339030cc889.filesusr.com/ugd/162fe6_d0b31801a2ff46bcaf2cda337e4f684c.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/0069b94a-a385-45f6-86ce-95ede13b85cb/nobimafawotiso.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3a056cba-7e16-42a8-82b8-3c4f4cb16d82/liperabe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/22c3aaaf-6788-4ab0-bbb9-aac84437cb35/ipad_mini_2_case_with_screen_protector.pdfIn PDF document text
    • https://8767aa75-4bd5-48c0-94ca-24e983238001.filesusr.com/ugd/debdc1_245be77d809c4c28bb4e06907948a449.pdf?index=trueIn PDF document text
    • https://a2876ee3-c470-454a-91e2-e108d831033a.filesusr.com/ugd/e8dba5_8fbcae49898d4a31b0fbcd809b1c5778.pdf?index=trueIn PDF document text
    • https://43cb2d18-1589-43a7-b1c5-fe1278e1c76d.filesusr.com/ugd/370b54_95edaeab00f84be6b11683ca9143207c.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_off0000fe5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE5B 5320 bytes
SHA-256: 8e902203ddcc21259261da9d822ab6e6d16d9ac45cf14e93e1a6fd152728942a
font_01_sfnt_off0001109a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1109A 10588 bytes
SHA-256: 781771197060a5257e7cfe3aa3f878aabc8d0af6c972ffbc7229dbe7f2744ea5