Malicious PDF — malware analysis report

Static analysis result for SHA-256 fae4e87406bcd2bd…

MALICIOUS

PDF

87.8 KB Created: 2021-06-30 12:49:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 893e06594392a0569b76570015c0f9bc SHA-1: 64b2a6c53421f366e3914a1293a64f3dda0e58c7 SHA-256: fae4e87406bcd2bd45a97bc8990f3fe0254ecacb9265fbad3396688dc950d5f6
96 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs that point to other PDF files hosted on compromised websites. This behavior is indicative of a link farm, likely used for SEO poisoning or to distribute further malicious content. The ML classifier strongly supports the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 5

  • 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://chcial.ru/uplcv?utm_term=sensation+and+perception+wolfe+3rd+edition+pdf PDF link annotation
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/a49aaefe955c0333fd0aa2db249f4122/fugutiliremo.pdfIn PDF document text
    • http://kme-kme.cz/files/file/47124491824.pdfIn PDF document text
    • http://winfielddeli.com/ckfinder/userfiles/files/mukejimafisalajosolo.pdfIn PDF document text
    • https://catwalkdogcome.com/editor_upload_image/file/10044882939.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f558b85fbd5a32e79c1d4d4d6e81ab07/bibakamapinevikifawigimo.pdfIn PDF document text
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a63f2b01480---55846636654.pdfIn PDF document text
    • http://vuatoyen.com/uploads/userfiles/file/garewixa.pdfIn PDF document text
    • http://africansafaris-spain.com/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/letewodajelilere.pdfIn PDF document text
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/qfgfosuguespaske0s72hagn16/77271876350.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab1ab81a6bc---zijobujisiwezib.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b9cf9330514---71313638460.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/90733c5b4b622a39d3efa6c036c77957/fuloj.pdfIn PDF document text
    • http://jagatjyotischool.org/jagatjyotischool/userfiles/file/84362695047.pdfIn PDF document text
    • http://easternsheep.by/app/upload/file/wewelemasidogixavum.pdfIn PDF document text
    • http://fusheng-vietnam.vn/admin/webroot/upload/image/files/69691885534.pdfIn PDF document text
    • http://buergerforum-tirol.at/file/13874004198.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/v2itmmk2s7g4sp6gn3chf3580h/83612095328.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b10743b098c---xitugonazovivafawirozixi.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606c86b1d1185---5845252123.pdfIn PDF document text
    • http://soles2walk.cz/data/file/nizetodozizavazam.pdfIn PDF document text
    • https://partner-support.net/user_data/userfiles/files/63504180539.pdfIn PDF document text
    • http://aiken7050.com/clients/5/51/510ae66c864a6d23552e02d1b5190e2c/File/nosifazewonij.pdfIn PDF document text
    • https://masini-de-ambalat.ro/images/userfiles/99424679373.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16088627fd697f---tagepekovukuvizivirul.pdfIn PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8d79cc0690---29476283957.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_off0000eee1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEE1 18292 bytes
SHA-256: 35a9f24e14565c37488835763508318ef14fabc4835ed9e50fca0638c0eb6930
font_01_sfnt_off00011f8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F8D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000137a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137A4 10948 bytes
SHA-256: 714ca7d632d7ea0eef5e7a29415a4094c6cd63deb5e86153ef883c7d411f0dd2