Malicious PDF — malware analysis report

Static analysis result for SHA-256 03ca9c2044981ed9…

MALICIOUS

PDF

83.0 KB Created: 2021-09-15 13:52:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: accc52b5f8d83cb9ab2c089053e2da9d SHA-1: f4acecc151818331bccad83d85fd9dbff9535d76 SHA-256: 03ca9c2044981ed9486416b0e6bfd3a6931325fabc28ea46117febb3fe500d25
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating it's a phishing or trojan distribution attempt. It contains numerous links, many pointing to compromised CMS upload storage and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URIs and the overall structure strongly suggest an attempt to lure users to external sites for further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://malagi.pl/user-files/fck/file/kipotavamuxalonivenato.pdf In PDF document text
    • http://edu-soft.ru/site/htmlimages/file/38619589093.pdfIn PDF document text
    • https://rts-wm.com/ckfinder/userfiles/files/65863351037.pdfIn PDF document text
    • http://archiwum.wyryki.eu/admin/ckfinder/userfiles/files/fegelem.pdfIn PDF document text
    • https://dalilak1.com/userfiles/file/88141643048.pdfIn PDF document text
    • http://cdn.eagle.mn/uploads/userfiles/files/mevofegugisamofidileramo.pdfIn PDF document text
    • http://ambvetsanprospero.eu/userfiles/files/riluxomobosibi.pdfIn PDF document text
    • https://areicon.com/images/file/givejonenopinem.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612ffa6798af9---bipixaroluxogi.pdfIn PDF document text
    • http://thucphamchucnangmy.vn/uploads/files/milidekaze.pdfIn PDF document text
    • https://skinrepublic.vn/webroot/img/files/pagolomituditinel.pdfIn PDF document text
    • http://tetrafluoro.com/upload/files/jalivizilo.pdfIn PDF document text
    • http://csc-vietnam.vn/uploads/userfiles/file/14560516341.pdfIn PDF document text
    • http://goodmax.ru/i/files/86602545587.pdfIn PDF document text
    • http://slesnick.net/userfiles/files/42118477823.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bf862e0fb0---31200908290.pdfIn PDF document text
    • http://stefani.cz/fck/file/22932965945.pdfIn PDF document text
    • http://dorrstrechy.cz/UserFiles/File/malejigumumurorumi.pdfIn PDF document text
    • http://esistore.com/userfiles/file/riwunegewegaseninexikexo.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134092386fd0---vokuteki.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/rejobazesam.pdfIn PDF document text
    • https://aokman-drive.com/d/files/juzurozuku.pdfIn PDF document text
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/b3pulc6c5vedqq47noaahp3r1s/wanarojesifidete.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=cwna+book+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_off0000e012.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE012 10204 bytes
SHA-256: fbf47f5c03f2b87d9ee9cbbf09328181655006754ae56eb3660fd00ed885f2ab
font_01_sfnt_off0000f6ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6EC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010efe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EFE 18216 bytes
SHA-256: 77a821e34f8857edd66dcba07366c4a9fe4db6ec63aa70440d901f129ecdcdfd