Malicious PDF — malware analysis report

Static analysis result for SHA-256 388f09ff1263f8eb…

MALICIOUS

PDF

70.4 KB Created: 2021-09-09 06:07:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: cc8f8490e8169b2ac83e6fffe326512d SHA-1: 2767e8fa176f09e154d08a693b5291a4ddc92d5e SHA-256: 388f09ff1263f8ebd64ec36328db3ce3220995dc93b75d660398c4585ce14ab7
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs, many of which point to disposable domains, indicating a link farm or phishing attempt. The ML classifier strongly flagged this PDF as malicious. While no scripts were directly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 4

  • 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://inwebjor.ru/uplcv?utm_term=malleus+maleficarum+pdf PDF link annotation
    • http://ecole.ru/text/images/file/57370708829.pdfIn PDF document text
    • https://www.tocbirsen.org.tr/ckfinder/userfiles/files/turalonizo.pdfIn PDF document text
    • http://bora.su/ckfinder/userfiles/files/wetakur.pdfIn PDF document text
    • http://ned.ru/uploads/files/62864994623.pdfIn PDF document text
    • https://highfieldhousehotel.net/nbloom/fckuploads/file/dapedibunikodajumili.pdfIn PDF document text
    • http://3bbb.fr/ckeditor/upload/files/49034451098.pdfIn PDF document text
    • http://aromamahabaleshwar.com/ckfinder/userfiles/files/7928124798.pdfIn PDF document text
    • http://interel-rus.ru/test/sites/default/files/file/46654030138.pdfIn PDF document text
    • http://westhollywood.ilovepokebar.com/uploads/files/xinofawaxutefeganegigi.pdfIn PDF document text
    • http://15449010.com/FileData/ckfinder/files/20210909_1581A631861E1D93.pdfIn PDF document text
    • https://hitpoint.tw/userfiles/file/17632254067.pdfIn PDF document text
    • https://harshahometutors.com/uniformkontakt/userfiles/image/files/dupixegoxex.pdfIn PDF document text
    • http://frangarcia.eu/upload/file/rukonerevunalem.pdfIn PDF document text
    • http://besteva.com/upload/files/4172487994.pdfIn PDF document text
    • http://www.samuitns.com/image/upload/File/88596162717.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/161385f12d367e---27816055544.pdfIn PDF document text
    • http://ukonlinedirect.com/userfiles/files/magutapetutexo.pdfIn PDF document text
    • http://saringkarnwood.com/UserFiles/file/5592569781.pdfIn PDF document text
    • http://kasintorn.com/images/upload/files/lofegir.pdfIn PDF document text
    • http://pyramidplaster.com/file_media/file_image/file/61015698483.pdfIn PDF document text
    • https://hogies.com/includes/template/uploads/file/75981102804.pdfIn PDF document text
    • http://khacvietlaser.vn/public/images_news/files/wipogug.pdfIn PDF document text
    • http://gruppocinofilomarsalese.com/userfiles/files/88091565449.pdfIn PDF document text
    • http://lyzjkgm.com/d/files/tupazowipuga.pdfIn PDF document text
    • http://j1medical.com/uploaded/file/95670521264.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_off0000b32b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB32B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB42 10552 bytes
SHA-256: 4ccb11b06f88292dab2091d171c2b437f94fe026709930e59913dac53278d013
font_02_sfnt_off0000e340.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE340 16028 bytes
SHA-256: 86c54190ddbb8f2e069762b607ec7c9b80f01a305515cd888f8fa857da7b8ab0