Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e40511f09a5662b…

MALICIOUS

PDF

81.3 KB Created: 2021-09-18 10:51:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 6a392da5db506e51ab6f59c8f2ec0e0e SHA-1: 8b0bf12830c674f8b322b9ca9ae817179cdb653b SHA-256: 8e40511f09a5662b723837e414a43ed7129786ab9df956bb7fb7f001a1d58f36
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many hosted on compromised or disposable domains, characteristic of a link farm designed to redirect users to malicious content. Heuristics indicate the presence of a link farm on compromised CMS uploads and disposable hosting, and ClamAV detected it as a phishing trojan. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://www.cbs-emballages.com/upload/file/vimon.pdf In PDF document text
    • http://mini-garden.ru/userfiles/file/vofoba.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/0no79ln9uco9jsjpip49hg22ej/10150585782.pdfIn PDF document text
    • https://apz-arte.com/ckfinder/userfiles/files/ximutirogifot.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/1613548ea725e6---13460973389.pdfIn PDF document text
    • https://hantverksakuten.se/ckfinder/userfiles/files/kadoguforuguduwakelede.pdfIn PDF document text
    • https://mma-montessori.com/admin/ckfinder/userfiles/files/78964570857.pdfIn PDF document text
    • https://dehayemek.net/upload/ckfinder/files/ralobevibodowukep.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16140518e0d5ae---33561042188.pdfIn PDF document text
    • http://bjhtdszdh.com/v15/Upload/file/2021917550307518.pdfIn PDF document text
    • http://toszegisuli.hu/userfiles/file/mavaru.pdfIn PDF document text
    • https://spbmworld.com/anaeter_capital/siteadmin/userfiles/files/rujilozizafumaxu.pdfIn PDF document text
    • https://china-glass-mosaic.vegner.com/userfiles/files/20210918_004343.pdfIn PDF document text
    • http://avrig35.ro/uploads/fck_editor/file/93141407503.pdfIn PDF document text
    • http://skidubravy.sk/spravca/ckfinder/userfiles/files/4580694387.pdfIn PDF document text
    • https://drosamahetta.com/userfiles/file/90128207723.pdfIn PDF document text
    • http://valkexclusief.reviews/app/webroot/files/userfiles/files/43716590602.pdfIn PDF document text
    • http://gidaero.com/upload/fckeditor/file/8324613390.pdfIn PDF document text
    • https://htapigroup3.com/contents/files/3775465383.pdfIn PDF document text
    • https://careersourcechipola.com/files/public/jisixux.pdfIn PDF document text
    • http://divorcefinance.nl/uploads/file/2693977486.pdfIn PDF document text
    • http://mudrkanuch.sk/editor_uploads/system/files/tifavupatukaw.pdfIn PDF document text
    • https://directorvincentchow.com/fck_filemanager_upload/file/zevitovazemubifuzo.pdfIn PDF document text
    • https://centrorevisionimonregalese.it/file/55375437993.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=best+multiplayer+games+under+100mbPDF 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_off0000d901.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD901 17280 bytes
SHA-256: 0c6bc5abee96d14c88bc027ccfb1e5f425bfdff0ab29ce664a84324b2cafe128
font_01_sfnt_off00010538.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10538 11196 bytes
SHA-256: 6be8c9e16bcbcf3566989fb8fa4fd69d6bf70a1a3ca803c02ac70fe4c792caab
font_02_sfnt_off00011f11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F11 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1