Malicious PDF — malware analysis report

Static analysis result for SHA-256 970e89c57582814a…

MALICIOUS

PDF

101.2 KB Created: 2021-08-01 11:37:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 472b774dd526e4505cb5e9861a52c418 SHA-1: f584f6e05228298b050afbdfd3a7ce4877e5ee79 SHA-256: 970e89c57582814ac150f30ff5a5f8e590ee351f9eda58b197f7a52155627cad
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised WordPress upload directories, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9931

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://gchsclassof1970reunion.com/clients/6/6a/6a45fbe13d63dbb0eb8070d7cb9dbc89/File/gevaropusurutixuko.pdf In PDF document text
    • https://surupaceanu.ro/ckfinder/userfiles/files/boguzaxo.pdfIn PDF document text
    • http://xaydungphongphu.com/uploads/files/6858405563.pdfIn PDF document text
    • https://www.duffylighting.com/wp-content/plugins/super-forms/uploads/php/files/1f344953332c32c5e3a44d50401aff23/94037291919.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9e4867658b---xapunezurakaxibidutifu.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ce0db059309---sexaju.pdfIn PDF document text
    • http://xn----8sbfeahwarn6ac1adp3fb2p.xn--p1ai/userfiles/file/8573369531.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e4980154204---boxowinifudelijeje.pdfIn PDF document text
    • https://bestofbucerias.com/upload/file/15723643791.pdfIn PDF document text
    • http://secretinvitation.net/images/files/zapelogijok.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c798e906e09---pokipiremuzux.pdfIn PDF document text
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/65f2281fb2072202128febc0e6239586/gamikowovojo.pdfIn PDF document text
    • http://synergytaekwondo.com/click2buy_newp/userfiles/file/51730797682.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/19599377193.pdfIn PDF document text
    • http://csc0731.com/userfiles/file/20210618234654_renj4t.pdfIn PDF document text
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/74c3e01d5ea06faaa71b8b663a56e079/45084451655.pdfIn PDF document text
    • http://inezorviskids.com/clients/37546/File/zogafoviputojodane.pdfIn PDF document text
    • http://burfel.ru/upfiles/files/teledezore.pdfIn PDF document text
    • http://newfieldclassof1982.com/clients/6/69/69e49ffade321d977af769e13f9f004b/File/kipedejakupiru.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abae39e34d7---bikizosibubovevemizewibav.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a3fb1e9b55a---50541283835.pdfIn PDF document text
    • http://ilyxrace.com/userfiles/files/mapunadudajonevixano.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/b490865d9144159470812f4915493860/42542723609.pdfIn PDF document text
    • http://cafemsoffice.com/userfiles/files/11766518238.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=how+does+sugar+concentration+affect+yeast+fermentationPDF 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://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_off000127ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127FF 18484 bytes
SHA-256: 8fe5a0c0f09542f6134a5e597462bb2d6a5deb2700fe7d45956569a72627b9b4
font_01_sfnt_off000158f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x158F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00017107.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17107 11064 bytes
SHA-256: 56d47af4070af68019463648606709b3d6215993ad126fee1a6d06cd886dd72f