Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fc5a6aac25da825…

MALICIOUS

PDF

82.6 KB Created: 2021-09-02 13:00:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: ec34992ae17053790c69266e62cd19b4 SHA-1: a33bfdfb9740fa7a386d6e7f856e2cd199bb94a3 SHA-256: 4fc5a6aac25da8257343cfce6f5816f358552f9e3d0bbca59847ac3de263391d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous links, many of which point to compromised WordPress sites hosting other PDF files. This behavior is indicative of a link farm designed to distribute malicious content or phish for information. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • 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 https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160757939d7d65---35628530907.pdf In PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160838af787636---83448949848.pdfIn PDF document text
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/839c6b065477e9f5e09887278eae2cf5/sititanutozav.pdfIn PDF document text
    • http://kientrucphatloc.com/upload/files/genejivebo.pdfIn PDF document text
    • http://sarljarry.fr/userfiles/file/duvogowimubu.pdfIn PDF document text
    • https://realestateconnect.biz/wp-content/plugins/super-forms/uploads/php/files/vhp4tc9u5bm1ed3ftk56devjo3/ritapamimizunolewitu.pdfIn PDF document text
    • http://gojjang.com/uploads/files/powabat.pdfIn PDF document text
    • https://nepalimodelagency.com/userfiles/file/72858456390.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/de5900c71a8cd85b15de1d3802258e77/fubiwuxoditebun.pdfIn PDF document text
    • https://freedomhypnosisnyc.com/wp-content/plugins/super-forms/uploads/php/files/85152c2c65aec32095a08784de31044f/suxepajexumoborofulopur.pdfIn PDF document text
    • https://vieclamlaocai.vn/webroot/img/files/zilexasitiwogitigol.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1607f17702f2d0---jetelivujuxoxitolamo.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f2d7a83d9b5---37198481271.pdfIn PDF document text
    • http://multi-accueil.fr/ressource/site-image/files/65831126526.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/e18a0bcec06e6e5d8c4a3f4b8080396c/41122578261.pdfIn PDF document text
    • http://uctodane.cz/UserFiles/File/28048195148.pdfIn PDF document text
    • https://xn--p3t29jo1ed4o4xw.tw/upload/files/navove.pdfIn PDF document text
    • http://doreenindiatours.com/userfiles/file/pixuwekezedimuzodefoxives.pdfIn PDF document text
    • https://growyourmoney.in/userfiles/files/59544122241.pdfIn PDF document text
    • https://baongochoa.com/upload/file/25773642450.pdfIn PDF document text
    • https://alexandrapanayotou.com/web/images/static/file/xonefapekezerofi.pdfIn PDF document text
    • http://xaydungphongphu.com/uploads/files/dipuvobife.pdfIn PDF document text
    • http://jinwoosmc.com/userfiles/file/97915352487.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/hlq75h94r689dbfboilc06qm6e/sewufazineradol.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=simple+english+essays+for+beginners+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_off0000de48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE48 11176 bytes
SHA-256: bc2894ae3528a76295b54594841b986177598581006e30411b7438eb9c6b422e
font_01_sfnt_off0000f7bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010fcd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FCD 17168 bytes
SHA-256: b99b1029c6e7e7d1bb16a9ff7fdd2b87733f982e1379dcd9bbdaad4605e03092