Malicious PDF — malware analysis report

Static analysis result for SHA-256 609a10486e002f10…

MALICIOUS

PDF

87.4 KB Created: 2021-09-19 02:51:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 884ec39c0546d8be5bc1b7202297315e SHA-1: 6f5ba78fecc32e3770b940b5ac3a9e749e4a960e SHA-256: 609a10486e002f101f44c0a42b6305196dde2eb7a2b52008fa0bb4589f3f665e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs pointing to external PDF files, suggesting a link farm or redirection mechanism to host malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a pattern of using disposable hosting for multiple links. No scripts were extracted, but the presence of external links is the primary indicator of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • 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 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 http://cungcapbaoduongcuanhatban.com/upload/files/wubepitiroli.pdf In PDF document text
    • http://mt-filtration.com/uploaded/file/2107370194613f8c9416306.pdfIn PDF document text
    • http://ijdssymposium.eu/upload/xuzizi.pdfIn PDF document text
    • https://stotex.rs/files/fapizelupu.pdfIn PDF document text
    • http://ingmontagna.com/userfiles/files/79970526468.pdfIn PDF document text
    • http://vector-mebel.ru/uploads/files/pozapifokuxu.pdfIn PDF document text
    • http://studiopiergentili.it/userfiles/files/vagukafidomif.pdfIn PDF document text
    • http://doctour.hu/uploads/ckfinder/userfiles/files/55057978345.pdfIn PDF document text
    • http://shesob.com/file/files/13608632145.pdfIn PDF document text
    • http://veszpremkosar.hu/_user/file/97382292816.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135087bcad07---mexozujajigusinonevus.pdfIn PDF document text
    • http://ceroki.com/image/files/5102095841.pdfIn PDF document text
    • http://www.propper-droppers.nl/files/file/77248437825.pdfIn PDF document text
    • http://feriaalainversa.com/uploaded/files/rodunamo.pdfIn PDF document text
    • http://mottaing.eu/userfiles/files/jakixexufivejikidi.pdfIn PDF document text
    • http://quatanggiabao.com/images/uploads/files/kazukiroz.pdfIn PDF document text
    • https://kientrucqhouse.com/uploads/image/files/54858769952.pdfIn PDF document text
    • http://westhollywood.ilovepokebar.com/uploads/files/milugasazugaletuji.pdfIn PDF document text
    • http://restravel.ru/ckfinder/userfiles/files/zatonobob.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/n9til60r9193l2kpor6iiti6ec/jabinaroxuvobilixepe.pdfIn PDF document text
    • https://ganport.pl/userfiles/file/73522960268.pdfIn PDF document text
    • http://xn--90aoa5aj.xn--p1ai/ckfinder/userfiles/files/baganefi.pdfIn PDF document text
    • http://www.mostenpo.jp/userfiles/files/fadaxefoxotajebedibuj.pdfIn PDF document text
    • http://ulv-fogger.es/d/files/zepasaverewugujijumumol.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=good+old+tetris+unblockedPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eea8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEA8 10572 bytes
SHA-256: fd76a53b6626df6682afe21340d4421d9ddb5cfdb5e91186e4d274a8ac3a2eba
font_01_sfnt_off000106ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106EA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011efc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EFC 18260 bytes
SHA-256: 2a8fd99ffffbbfa72199c52859efcd70335e80a2894865ade3391c1ae7d0be4e