Malicious PDF — malware analysis report

Static analysis result for SHA-256 af3038bca394c523…

MALICIOUS

PDF

83.1 KB Created: 2021-10-04 22:21:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 9e98f528edce861cfac60c58113261e8 SHA-1: 19cff806d7fc050f0338d6017c6aa79b3c0243b6 SHA-256: af3038bca394c5236422445da817dfc93cd77d593d6b50a22f33e29bb9ffb73c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It functions as a link farm, containing numerous URLs pointing to various domains, some of which are hosted on compromised CMS platforms. The presence of these links suggests an intent to redirect users to potentially malicious websites for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://oniceh.ru/uplcv?utm_term=unsigned+binary+subtraction+using+2%27s+complement PDF link annotation
    • https://www.karelo.com/uploads/File/dulelidefo.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/d89553c462b115a84bd0b5733c3bae83/mutuvevotumiragegovobewaw.pdfIn PDF document text
    • https://uangraja.com/contents/files/buxoxoxoramapobanuro.pdfIn PDF document text
    • https://www.greenlakecruises.com/ckfinder/userfiles/files/54076331958.pdfIn PDF document text
    • https://www.speeddating.lt/speeddating/ckfinder/userfiles/files/kadefakowezipimefi.pdfIn PDF document text
    • https://biocenfis.es/uploads/assets/file/vavegum.pdfIn PDF document text
    • http://balade-pierry.fr/userfiles/file/rovaletutujit.pdfIn PDF document text
    • http://wamer.org/userfiles/file/92811360001.pdfIn PDF document text
    • https://rheinfurth.de/userfiles/file/vogusaluloxixanapenidalok.pdfIn PDF document text
    • https://goodluckfishing.com/ckfinder/userfiles/files/pupitaxikaxejakip.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614d6fb28297d---62421410305.pdfIn PDF document text
    • http://zhfangyuan.com/uploadfiles/files/67922462456.pdfIn PDF document text
    • http://760_709737661.mildmedia-dev.eu/uploads/userfiles/files/fejiresetobubagupumet.pdfIn PDF document text
    • https://asi-filter.pl/files/file/jagufesomutegebo.pdfIn PDF document text
    • http://satyavnetworks.com/fck_upload_images/file/podokaguvos.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615a58783a90a---tibadazaxanisefesuru.pdfIn PDF document text
    • https://itscebu.com/upload/file/20210925093247.pdfIn PDF document text
    • http://razzledazzleevents.in/userfiles/file/51679011790.pdfIn PDF document text
    • http://bassonconsulting.mc/userfiles/file/vuxigigenejatipoluketo.pdfIn PDF document text
    • https://advance-pack.com/editor_upload/file/76301995537.pdfIn PDF document text
    • https://avistravel.ro/userfiles/file/jodugopaw.pdfIn PDF document text
    • http://bn-biz.com/userData/board/file/nenovikabanenerojesaf.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_off0000d83c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD83C 11372 bytes
SHA-256: 6447be5fa4d15e558a6ed2d0d9a08db853611e1152855df2e2698cd037a69580
font_01_sfnt_off0000f2ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2BA 19672 bytes
SHA-256: 390d1718af712c79c02038bc5f4daeb451bc1179e47ce5058813ab75b358cfa5
font_02_sfnt_off00012699.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12699 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1