Malicious PDF — malware analysis report

Static analysis result for SHA-256 31ccd06ef1828389…

MALICIOUS

PDF

72.3 KB Created: 2021-09-10 08:08:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: b6341ee61d0db18c97e17a62ea218917 SHA-1: 9ea0876e6cc5eeb37f2bd167877e21ef03cd8ea3 SHA-256: 31ccd06ef18283897a1e3dab540fb9fd63964301a65baa66d701567878d39487
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. It contains numerous embedded URLs that point to disposable hosting and are likely used to redirect users to phishing sites or download further malware. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically identifies the document as a link farm designed for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 5

  • 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 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://krisoc.ru/uplcv?utm_term=watch+friends+online+with+subtitles PDF link annotation
    • http://amongelite.com/ci/userfiles/files/total.pdfIn PDF document text
    • http://kaymccarthy.com/immagini/file/43727730886.pdfIn PDF document text
    • https://ratodua.com/contents/files/21158864259.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/54272253742.pdfIn PDF document text
    • http://pajurioverslas.lt/ckfinder/userfiles/files/pukipad.pdfIn PDF document text
    • https://suavitinhtannha.net/upload/files/73089685230.pdfIn PDF document text
    • http://bebaldebaran.eu/userfiles/files/begolek.pdfIn PDF document text
    • http://www.moyekolodin.com/files/devubak.pdfIn PDF document text
    • https://theloneranger.tv/clients/loneranger/ckfinder/userfiles/files/48150922413.pdfIn PDF document text
    • http://climtech.com/files/files/poxafodebini.pdfIn PDF document text
    • http://quincy.pl/ckfinder/userfiles/files/45137004649.pdfIn PDF document text
    • https://florissantdesign.nl/docs/Image/file/vebajesovoben.pdfIn PDF document text
    • https://betalinktech.com/blmedia/file/kularepexawixitepuruj.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/futusafoluvi.pdfIn PDF document text
    • https://somogyplusz.hu/files/24014004070.pdfIn PDF document text
    • https://aynispirit.nl/userfiles/file/46951816061.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138543ae45fc---41702164787.pdfIn PDF document text
    • http://eachfun.com/ckfinder/userfiles/site_eachfun_com/files/36878890267.pdfIn PDF document text
    • http://ehomerealestate.org/images/file/jukiluzexedetebudanogej.pdfIn PDF document text
    • http://yaan121.com/uploads/files/202109041057467179.pdfIn PDF document text
    • http://bradzo-ep.com/uploads/files/62875669622.pdfIn PDF document text
    • http://daglichtfilters.nl/ckfinder/userfiles/files/fugiwofetirefaleririvusu.pdfIn PDF document text
    • http://alpes-de-haute-provence.proximeo.com/ckfinder/userfiles/files/72941295908.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161342147bee5e---50228178998.pdfIn PDF document text
    • http://sattosushi.com/uploads/files/89729140617.pdfIn PDF document text
    • http://tprcindia.com/ckeditor/ckfinder/userfiles/files/34939875244.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://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_off0000b507.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB507 10892 bytes
SHA-256: e77c23269003533bfdd53f06b4bd75b91034e51746453e29798ed6f1dd160bc0
font_01_sfnt_off0000ce3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE3F 17644 bytes
SHA-256: 7257f9002a128ed128cf40bbe421d94f6921fab7becba185886bbc0b2923107d
font_02_sfnt_off0000fb79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB79 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1