Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c668c78776664c0…

MALICIOUS

PDF

83.8 KB Created: 2021-09-07 18:04:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 346c4ff5ada6e29e241a4842f38bb15c SHA-1: b531ba6ba88a65a9ade4cbe315c15fc0b3be148a SHA-256: 3c668c78776664c02d8f388a026898eef85ad7fa048fc818f1b02fe11b25d402
96 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised CMS uploads or disposable hosting. The ML classifier also flagged this PDF as malicious with high confidence. The primary function appears to be acting as a link farm to redirect users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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 http://romengo.com/ckfinder/userfiles/files/95898995213.pdf In PDF document text
    • https://ajitcoatings.com/uploads/16749441767.pdfIn PDF document text
    • http://srividyaastrology.com/userfiles/file/59539494661.pdfIn PDF document text
    • http://cuanhuadanang.vn/uploads/image/files/vulevebupixamavimi.pdfIn PDF document text
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/286hrvfk394qr3qf1gf9cdaop8/5841272828.pdfIn PDF document text
    • http://recko.ru/ckfinder/userfiles/files/galupiroginilevu.pdfIn PDF document text
    • http://camionespanamericana.com/userfiles/file/bafarafaneduwo.pdfIn PDF document text
    • https://stdtekstil.com/upload/ckfinder/files/pepujuxafufewusafuzawege.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/1f419bfd5df616656fa97b8dc6e0c5f8/9114249192.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/23669430610.pdfIn PDF document text
    • http://globalquestconsulting.com/userfiles/files/85768156445.pdfIn PDF document text
    • http://aimic.com/userfiles/file/62987394914.pdfIn PDF document text
    • http://studionegro.net/userfiles/files/55773006449.pdfIn PDF document text
    • http://gamboeng.com/assets/ckfinder/userfiles/files/wevidumodimulakolanerulek.pdfIn PDF document text
    • http://fbhsclassof70.com/clients/f/f6/f6e65d48c6cf753e26882f86001d336b/File/74992553777.pdfIn PDF document text
    • https://dcimx.com/files/44711681838.pdfIn PDF document text
    • http://thepokewave.com/uploads/files/9914815095.pdfIn PDF document text
    • https://amrapalispot.com/userfiles/file/zaxejirabuwexerukafam.pdfIn PDF document text
    • http://mynigaoe.com/upload/file/20210524215859.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/lu1fsm0kihhmnll9t8ompgtual/41572076241.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/zusipadenalokupisova.pdfIn PDF document text
    • https://skvely-kup.cz/files/file/difugudinepulumariwax.pdfIn PDF document text
    • http://jarosi.hu/files/file/nibogopamul.pdfIn PDF document text
    • http://bertoniamministrazione.it/bertoni/public/file/doxorinuvuwaxosopodir.pdfIn PDF document text
    • https://dodatnojamstvo.com/userfiles/file/taraz.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d35d25ef262---20192310897.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=passages+1+3rd+edition+pdfPDF 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_off0000db3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB3A 20056 bytes
SHA-256: b9dee12846312c78ad15f71bdc1de2a2e9f6fccf1a00d33867b4d940d60036a1
font_01_sfnt_off0001108c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1108C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000128a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128A3 10852 bytes
SHA-256: eab4446e24f67dd1186b01edb4cbc3d52433939c2b9c2d749a285b52477797af