Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd0982ec9898a1c4…

MALICIOUS

PDF

88.0 KB Created: 2021-10-04 23:45:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 3adc88531ffb5ff7b9d1b634f6e1adb1 SHA-1: 82e32fbed11caba465c0d08b6c20f951e01d2d8c SHA-256: bd0982ec9898a1c4174bdfd1a7082b473c2be30b4bfd7acd4a708d6520b52ae2
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which are part of a link farm hosted on disposable or compromised domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://s13cf5ef.alojamientovirtual.com/ropalaboralbarata.com/userfiles/file/peletazubalo.pdf In PDF document text
    • http://refinerlink.com/userfiles/file/kozudowetunebesuritifif.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/16143afc3d817e---14556587061.pdfIn PDF document text
    • http://altinay-law.com/images/file/kivovutavop.pdfIn PDF document text
    • http://stjconsulting.it/userfiles/files/2207651321.pdfIn PDF document text
    • http://mastrodibaglio.it/userfiles/files/94104230032.pdfIn PDF document text
    • http://glavis.biz/userfiles/file/kefadupode.pdfIn PDF document text
    • http://underbutter.cz/download/foto/nixorimaliponawipojipixom.pdfIn PDF document text
    • https://kratky.eu/files/file/dosugewesofoxi.pdfIn PDF document text
    • http://alanaf.ru/userfiles/files/rokumokafabes.pdfIn PDF document text
    • http://dailyliving.nl/ckfinder/userfiles/files/sajavop.pdfIn PDF document text
    • http://okna-dvere-online.cz/media/upload/upload/file/pakisatudulupoku.pdfIn PDF document text
    • http://tokyosushilohaus.com/uploads/files/8209294452.pdfIn PDF document text
    • http://czernavendeghaz.hu/admin1/file/10520945331.pdfIn PDF document text
    • https://chinatupai.com/web/js/ckfinder/userfiles/files/pijerididajosobok.pdfIn PDF document text
    • https://doctornhospital.com/banglanews24/editorsfiles/files/xisenibilesam.pdfIn PDF document text
    • https://propertiproperty.com/Uploads/userfiles/files/76854314836.pdfIn PDF document text
    • http://epoch-making.jp/js/upload/files/mazexonijomatudofitof.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1615867cec6f51---96367939737.pdfIn PDF document text
    • https://svarovanijelinek.cz/ckfinder/userfiles/files/natugisivewejug.pdfIn PDF document text
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/1615422eeb10d3---wilazidanog.pdfIn PDF document text
    • http://captainkillmite.com/uploads/files/202109082029169062.pdfIn PDF document text
    • https://luatkhangthai.vn/upload/fck/file/60119680066.pdfIn PDF document text
    • https://biodent.ro/m4fm_files/m4news/ck-uploads-files/94826534621.pdfIn PDF document text
    • http://www.vandiestbrandstoffen.be/uploads/files/90205056590.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=invertebrates+with+jointed+legsPDF 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_off0000ef67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF67 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010779.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10779 19264 bytes
SHA-256: 2bfa4dd5e82bbbdc7ea779cace053db294f42718cccb1aa909a70b385ae23ea1
font_02_sfnt_off0001390f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1390F 10900 bytes
SHA-256: 3221e897b23efc6f36588bd5ab93730cc2ded949ca1cc801d68dfa671a81c0d8