Malicious PDF — malware analysis report

Static analysis result for SHA-256 33c7ec68696a8b36…

MALICIOUS

PDF

83.1 KB Created: 2021-04-23 07:09:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 6e19a86b9214a87653b794fcbcb6efaf SHA-1: 2215f65bda1cb39bd1c7f536a8cafe3eacbd6d61 SHA-256: 33c7ec68696a8b36d4a7038c114629ad35641b049a543009c37ef0440b5ba6ad
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, indicating it functions as a link farm. Several heuristics, including 'PDF_SEO_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM', confirm this behavior. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution through these external links. No scripts were extracted, but the primary attack pattern involves directing users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://resalured.ru/strik?utm_term=why+is+ralph+waldo+emerson+important+when+we+consider+american+literature PDF link annotation
    • https://beperupofifu.weebly.com/uploads/1/3/1/6/131636755/zisapexas-norufo.pdfIn PDF document text
    • https://sofodifimujinem.weebly.com/uploads/1/3/4/2/134234674/231115.pdfIn PDF document text
    • http://nasumowuvajoda.iblogger.org/beethoven_s_5th_sheet_music.pdfIn PDF document text
    • http://jokegave.mywebcommunity.org/rosadurawipuv.pdfIn PDF document text
    • https://wisokovunali.weebly.com/uploads/1/3/6/0/136051549/werajorud-pekegogesog-ridoxatir-zudeluvowi.pdfIn PDF document text
    • https://mifurujuxix.weebly.com/uploads/1/3/3/9/133997148/3924095.pdfIn PDF document text
    • https://lapulefad.weebly.com/uploads/1/3/2/8/132815180/8317321.pdfIn PDF document text
    • https://kepubewi.weebly.com/uploads/1/3/6/0/136095452/kumir.pdfIn PDF document text
    • https://wujadadi.weebly.com/uploads/1/3/1/0/131070572/9987118.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://01dc7cc6-b8ed-446e-8cc8-1ad78882ed38.filesusr.com/ugd/e23fbb_5fee953156cf4d8194af7f61d96cf299.pdf?index=trueIn PDF document text
    • http://tuwewigeniwaf.rf.gd/breathe_in_cash_out.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/41ecef7f-3263-435f-aa18-d6156dd68cc5/38578006054.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d093ea10-adc8-4cf2-a780-1fa087686932/how_do_you_fix_a_garage_door_opener_that_wont_close.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/943a7976-63dd-4937-ae47-9b3a4bc58171/23635086355.pdfIn PDF document text
    • http://fajenadiwizowo.atwebpages.com/5560194534.pdfIn PDF document text
    • http://surotatifezuxe.rf.gd/57334410079.pdfIn PDF document text
    • http://duziroro.myartsonline.com/29708012767.pdfIn PDF document text
    • https://9ef77391-fdd1-48d8-ba15-364b07375333.filesusr.com/ugd/ebefdf_8afabadc05fa44cc8368393044b136fd.pdf?index=trueIn PDF document text
    • http://mumufikoxid.epizy.com/jaxesi.pdfIn PDF document text
    • http://nodefojabotozij.rf.gd/jifewunewuxanuve.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/158eaf69-dbf9-40ca-bc93-4c8a87218abb/epson_xp-200_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/81ac94fa-10cd-403b-b21e-6269e892dcc3/furiously_happy_jenny_lawson.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fa52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA52 5404 bytes
SHA-256: 5944976e2a6ea9a7d7cc0ec0512f06e448966b96b01fbe4860123401880b8469
font_01_sfnt_off00010c9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C9F 10428 bytes
SHA-256: c808477eb5c7977cd3a2c777732b3001da01d91f6a0743a85ac38268209784ed
font_02_sfnt_off00013017.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13017 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2