Malicious PDF — malware analysis report

Static analysis result for SHA-256 395672bf6285f333…

MALICIOUS

PDF

90.6 KB Created: 2021-07-23 00:05:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3d57321e9f04a46041cfe08b51f3bfe6 SHA-1: 88acabda5267024d99fc51ced3782dcc8bf5bbb1 SHA-256: 395672bf6285f3339417da45054abc07cfb46940767490653c1283293568deb8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is identified as malicious by ML classifiers and ClamAV, with high confidence. It functions as a link farm, directing users to multiple external URLs, many of which are hosted on compromised or disposable domains. The PDF structure and embedded links suggest an attempt to redirect users to malicious content, likely for phishing or to facilitate the download of additional malware. No scripts were extracted, but the PDF's nature points towards T1566.001 (Spearphishing Attachment) as the likely initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://celyroknaterase.sk/editor_uploads/system/files/37239388295.pdf In PDF document text
    • http://prtourusa.com/FileData/ckfinder/files/20210723_EA969A33595364A0.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/ild22hbpdr2lioom51fsv2eno7/58888200784.pdfIn PDF document text
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a0f9d6272ae---jibifan.pdfIn PDF document text
    • http://bannermaul.com/userData/board/file/bujabetifefijar.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1609df2e59baf8---32062694973.pdfIn PDF document text
    • https://prawobrzeze.info/userfiles/file/zijezuwu.pdfIn PDF document text
    • https://bulgariapools.com/contents//files/63823573566.pdfIn PDF document text
    • http://sbstroy53.ru/img/files/61340570208.pdfIn PDF document text
    • https://smlstripedbass.com/home/rock/public_html/ckfinder/userfiles/files/37491798695.pdfIn PDF document text
    • http://sportingclubalbinia.eu/userfiles/files/72601571766.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8bfa16204---92406215986.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/b374ce1fcff88731b79a7c19c497c28b/60508021588.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac3ed1061dd---44335579710.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097eeb1f3680---93547726437.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/50ec43bca5c303990fc79ad1fe3b9944/3039114603.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/aro39p409ar1m2fk06dn2i2llv/tisiraseparijakele.pdfIn PDF document text
    • https://www.mnspineandsport.com/wp-content/plugins/super-forms/uploads/php/files/b6e093df8d3ab9ab144ff1fc6568ac02/71649517613.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/fjft0u2cato4r90bq56loe69m5/retakewakizit.pdfIn PDF document text
    • http://reutlinger.pl/userfiles/file/nariduvalosexazisafi.pdfIn PDF document text
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/adc532d998da68390617e131a8e7e3c4/kuduxivipopanigosovag.pdfIn PDF document text
    • https://cualuoihoanmy.com/uploads/userfiles/file/zojizi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+remove+magnetic+clip+from+clothesPDF link annotation
    • http://mustang.tom.ru/jsplugins/ckfinder/userfiles/files/tolunitirodexu.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_off0000fd64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD64 17104 bytes
SHA-256: be52b0eece91f5ce69c5d7303fcdaf5fe136cf86bc3bca37cca59a8518644cef
font_01_sfnt_off00012a15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A15 11072 bytes
SHA-256: 0aa7f3a919127d0e5bcaad3ac49c5ecfeaa83e5ead37f6ee5cc4ed5d5d0635c3
font_02_sfnt_off000143b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x143B9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1