Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a865d4fd77389b9…

MALICIOUS

PDF

78.2 KB Created: 2021-09-21 08:16:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 49183fdfc68faad43f3d31c565639ad7 SHA-1: bf8244a527e344d8ff1d0a83514b706df852e631 SHA-256: 7a865d4fd77389b9f23998cdfcbeb610160cd1a3a64d4c05f695ecc5539af615
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and embedded links are indicative of a malicious document, potentially leveraging JavaScript for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6125

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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://vinhhangvien.com/upload/files/13571641044.pdf In PDF document text
    • https://idea-web.ro/app/webroot/files/userfiles/files/75384653049.pdfIn PDF document text
    • http://sity-luxe.ru/userfiles/file/tovonemuripozejabake.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613e427becd2e---tuxoderuroti.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16144ca9a3d6b1---77054362563.pdfIn PDF document text
    • http://scouttautomotive.com/editor_uploads/system/files/zitefo.pdfIn PDF document text
    • https://akapacha.com/userfiles/file/jofazelozo.pdfIn PDF document text
    • http://nagyberki.hu/sites/default/files/fck_uploads/file/kodidiv.pdfIn PDF document text
    • http://cgmorenanews.com.br/ckfinder/userfiles/files/lijatumazolexesig.pdfIn PDF document text
    • https://shih-tzu.ro/files/file/70227599117.pdfIn PDF document text
    • http://daotaonhaccong.com/uploads/userfiles/file/nijejelififem.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/55c2e32488c2d998f8418c54d1f02056/renazenugepomat.pdfIn PDF document text
    • http://wuyioutdoor.com/userfiles/file/8376504987.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/kf6olg4pmdkivnmohrs7fsr3c7/fizafivawewifuvokowa.pdfIn PDF document text
    • http://studiotipaldo.com/userfiles/files/sirovewomewevuxuvuge.pdfIn PDF document text
    • https://kolegium.inaheart.org/upload/files/11643896824.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/16135f490d2d6e---nudafusogixuvitapi.pdfIn PDF document text
    • http://almawred-sy.com/files/adminfiles/files/guperojenadovapodidago.pdfIn PDF document text
    • https://hantverksakuten.se/ckfinder/userfiles/files/50876291476.pdfIn PDF document text
    • https://demircanticaret.com/userfiles/file/latabosatefix.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/m6r0lee9bn78dtb99a5s37en8j/naniburofej.pdfIn PDF document text
    • http://speednewslive24.com/assets/ckfinder/core/connector/php/uploads/files/xotiwe.pdfIn PDF document text
    • http://retailcop.ca/files/witer.pdfIn PDF document text
    • http://movitecnic.fr/ressource/site-image/files/67906332263.pdfIn PDF document text
    • http://king-pro.com/userfiles/files/59094134348.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=view+private+instagram+online+freePDF link annotation
    • 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_off0000d7a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7A8 17976 bytes
SHA-256: 703f963f520fe4b0476d660a329d42c4ffbe7eea8b10e5b8da0519ef1721c11d
font_01_sfnt_off000105af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105AF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011dc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DC6 10824 bytes
SHA-256: e9d618a69d1c55b1aaf4a056c122a06b31cbe96d6ed90ef9c91ac0b686e27230