Malicious PDF — malware analysis report

Static analysis result for SHA-256 4af4689ac8c71cd2…

MALICIOUS

PDF

86.8 KB Created: 2021-10-10 13:28:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 05e6fa09745ca6adee497c3cd430fd2d SHA-1: 250a3b7fc191b6b840e318dd1b06e3a365d085f7 SHA-256: 4af4689ac8c71cd2de59456c7f274abd376d9fa13e456c42d42eaecd8adf5d08
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of link farms designed to obscure the final destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple external URIs and link farm heuristics supports the classification as a malicious link distribution mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://cructi.ru/uplcv?utm_term=the+cliff+resort+%26+residences
    • http://kingsbrite.com/kingsbrite.com/userfiles/file/fifowotokumevazi.pdf
    • https://spbmworld.com/anaeter_capital/siteadmin/userfiles/files/98050388494.pdf
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/512571324fe2cb3b0064366ab7db59d9/xigaxetasirotuso.pdf
    • http://mariamozharova.ru/uploads/files/sirozixanadubav.pdf
    • http://jjkxmy.com/upload/files/202110081817067142.pdf
    • http://adbuilder.at/ckfinder/userfiles/files/sutisakedafinepinugorat.pdf
    • http://sutipatika.hu/userfiles/files/valajikamodemonavi.pdf
    • http://dental-forum.ru/userfiles/file/80987048579.pdf
    • https://www.frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/bejotebar.pdf
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/207c7ada0c254ee8b032de9dc540cae3/setibawazilitidolu.pdf
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614de573e666c---7479503556.pdf
    • http://chornakorn-packing.com/ckfinder/userfiles/files/95345924574.pdf
    • http://homeloanz.net/images/e/file/pumaziwugimomopowezitix.pdf
    • http://canxetaidientu.com/images/file/48599389979.pdf
    • https://27061010.com/uploads/files/202109301156282991.pdf
    • http://www.jfac.kr/ckfinder/userfiles/files/leruzinisal.pdf
    • https://profipreklady.cz/www/ckfinder/userfiles/files/baredijojurubigaledete.pdf
    • http://www.ecrivains-consult.fr/easyonline/ckfinder/userfiles/files/lerinosetevevisodi.pdf
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615b0d7630828---kepikudilisexasobuwufa.pdf
    • https://ckmusicdesign.nl/userfiles/file/58757731476.pdf
    • http://suyogmaratha.com/editorimages/file/tanageji.pdf
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/16160f99594052---19148441802.pdf
    • https://tktravelkorea.com/FileData/ckfinder/files/20210902_1F670DB56757E6FB.pdf
    • http://firegallery.ru/img/upload/91852215804.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e6f1.bin
c5a9ba103908e254f0bd33ed04a1d03547cad3c84689b82b9629a711b398cafe
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6F1 10128 bytes
font_01_sfnt_off0000fdb2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFDB2 16792 bytes
font_02_sfnt_off000115c4.bin
bfd8987915ffc6239c81e9cbed0c99be2a74802da7482a9c24efd88a310fbd58
pdf-font-stream PDF embedded font (sfnt) at offset 0x115C4 21008 bytes