Malicious PDF — malware analysis report

Static analysis result for SHA-256 39b74ef037dd03f3…

MALICIOUS

PDF

77.3 KB Created: 2021-09-19 14:53:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 0e31ccb7058b7637564f0f825b1d84e9 SHA-1: 1e6a3732a932370d795a219f946a89ba70326049 SHA-256: 39b74ef037dd03f30b85940ddc905b4f3caa0df7b91f52e580367bc3165ad303
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to potentially compromised websites or disposable hosting, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The presence of external URI heuristics and link farm indicators supports the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://nbc.ua/design/pic/file/16485932586.pdf In PDF document text
    • http://miyagi.chi-kara.net/Upload/files/32691777492.pdfIn PDF document text
    • http://backkwang.com/userData/board/file/butoxivoxagu.pdfIn PDF document text
    • http://volkshilfe-vlbg.at/images/content/files/4749522847.pdfIn PDF document text
    • https://saatyapi.com/upload/ckfinder/files/pagevukumubenumosovapona.pdfIn PDF document text
    • http://studionegro.net/userfiles/files/53215728255.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614080cc36b04---68657983534.pdfIn PDF document text
    • https://barcelonamedicalcenter.com/files/galeria/files/tekibekepefizozej.pdfIn PDF document text
    • https://ryokanclub.com/FileData/ckfinder/files/20210916_3632E3B57C7C7AE7.pdfIn PDF document text
    • http://achwvs.love-mrt.com/upload/files/wanozoruzux.pdfIn PDF document text
    • http://smsgurugram.com/miet/assets/files/budavapulapusenosofoli.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e08d4e6514---8187847971.pdfIn PDF document text
    • http://ejmk.com/ej/upload/files/mupozokomojila.pdfIn PDF document text
    • http://barcelonasixtytwo.com/userfiles/file/lagisefanozixi.pdfIn PDF document text
    • http://kozhencherrymtc.org/userfiles/file/dusakemawanozeker.pdfIn PDF document text
    • http://dgxzz.com/uploadfile/file/67399148382.pdfIn PDF document text
    • https://immsac.pe/sgi_userfiles/userfiles/files/69856717884.pdfIn PDF document text
    • https://washlounge.in/ckfinder/userfiles/files/11170833828.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161332bd58b5f2---popoviweloferus.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e23e02868e---56443161046.pdfIn PDF document text
    • https://wfca-czech.cz/temp/userfiles/files/kawesogipiwir.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/8566424fc561e07cb7489ffef66667cf/50502691551.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/161455b3532303---jupuzewexonipuk.pdfIn PDF document text
    • http://collectifff.be/imgdb/accueil/files/wagawe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=hurt+quotes+for+himPDF 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_off0000cc7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC7B 10404 bytes
SHA-256: 67e81344087e9727de6c06c9bed01516603e8e009780eb91f39e85c3063de9ea
font_01_sfnt_off0000e3fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3FE 16752 bytes
SHA-256: bb8b0ffbc4f29376ae83a48b7b14e127d05e3b958114a050b288f3759ef1bdf8
font_02_sfnt_off00010f65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F65 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1