Malicious PDF — malware analysis report

Static analysis result for SHA-256 a386154fec85ad37…

MALICIOUS

PDF

74.9 KB Created: 2021-09-17 03:28:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: d1a93cbd20ae9df9603203296ca92e4b SHA-1: 81fa7c93dc1d966481c97cd2d5c5cf16f235755d SHA-256: a386154fec85ad374f566365f5665589705000107201b3e84f26f275764ae3bd
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with multiple embedded URLs pointing to other PDF files. The primary purpose appears to be directing users to a network of sites, potentially for SEO poisoning or to serve as a distribution point for further malware. No scripts were extracted, but the PDF structure itself suggests malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://elsped.hu/files/file/86426842079.pdf In PDF document text
    • http://clinicaveterinariailmarzocco.it/userfiles/files/27320072804.pdfIn PDF document text
    • http://iact2001.com/userData/board/file/9426485802.pdfIn PDF document text
    • http://mjengo.org/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/gegunexinakavaj.pdfIn PDF document text
    • http://robfredo.com/userfiles/file/figuzaxorazetibogumevuli.pdfIn PDF document text
    • http://bhk-aindling.com/userfiles/files/25500859727.pdfIn PDF document text
    • http://gardenofsound.com/userfiles/files/geraniwo.pdfIn PDF document text
    • http://pinedafoundation.org/imageuploads/file/59993527132.pdfIn PDF document text
    • https://mytekas.com/UserFiles/file/fejogosus.pdfIn PDF document text
    • https://sunridgecorp.com/uploads/files/202109160920126273.pdfIn PDF document text
    • https://paulogomeslda.com/userfiles/file/28143388763.pdfIn PDF document text
    • http://020tzs.com/baige/images/userfiles/file/rodidudetufugudonifuso.pdfIn PDF document text
    • http://wonderpanel.com/app/webroot/img/file/94130662097.pdfIn PDF document text
    • http://langmypham.com/luutru/files/jifozibowejez.pdfIn PDF document text
    • http://abnigakgdsg.friendship-match.com/upload/files/nalav.pdfIn PDF document text
    • http://tieclangman.com/Images_upload/files/wodifexuwaluride.pdfIn PDF document text
    • https://egyptsuntours.com/userfiles/files/dazox.pdfIn PDF document text
    • https://ethnicminorities.heephong.org/ethnicminorities/cmsadmin/ckfinder/files/77810930390.pdfIn PDF document text
    • https://jensbrode.de/files/file/49983715458.pdfIn PDF document text
    • http://likuidart.com/files/ckeditor/files/gineduwukixiku.pdfIn PDF document text
    • http://omatsuri.kr/data/userfiles/files/92921631084.pdfIn PDF document text
    • http://yao-cheng.com/uploadfiles/20210904102736.pdfIn PDF document text
    • http://lamarchesainterita.be/lamarchesainterita/imgdb/news/files/nogobofuvoj.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/16143c5b937d62---gikarofobigulalowibataw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=anime+tube+apk+latest+versionPDF 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_off0000c2e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2E9 10792 bytes
SHA-256: acb9b9b09923cb88460edcf1ae14ad4fe51f0999377b04c78ec91adfb5a4d24d
font_01_sfnt_off0000db95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB95 16384 bytes
SHA-256: 0cb9c4a7ee9d71daac13b4676a0ccd861915ec5446151bfa20e2af317dea8b34
font_02_sfnt_off00010583.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10583 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1