Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb2581bf1d603ba4…

MALICIOUS

PDF

71.3 KB Created: 2021-10-02 16:29:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b2ac3baa6c73cb2312c9107f9681446f SHA-1: 3304ebfd59f88824fad11dc837155757aaf706c0 SHA-256: fb2581bf1d603ba4398df35d85c77cd5622b6441dcb8a605663bf225dcef30f4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or are part of a link farm on disposable hosting, indicating a phishing or redirection attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, potentially leveraging embedded JavaScript for malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://nomylo.ru/uplcv?utm_term=parents+dua+for+child+in+arabic PDF link annotation
    • https://stpatswatertown.org/ckfinder/userfiles/files/79168050458.pdfIn PDF document text
    • http://www.web-globus.de/ckfinder/userfiles/files/3019330719.pdfIn PDF document text
    • http://stacjaregeneracja.pl/userfiles/file/latuba.pdfIn PDF document text
    • http://steinemann-ag.ru/44197959263.pdfIn PDF document text
    • http://kajo-frings.de/userfiles/file/31894155351.pdfIn PDF document text
    • http://ornito-silesia.eu/userfiles/file/5819638875.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16155ed0c770bb---2024204958.pdfIn PDF document text
    • http://lecieldesandes.fr/ckfinder/userfiles/files/pesixep.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/3ba6c9c106dc7d928083f298462e38fe/benawedixesaduxomiwijamid.pdfIn PDF document text
    • https://yensaovinastar.com/media/files/70330330103.pdfIn PDF document text
    • https://phoenixknights.co.uk/wp-content/plugins/super-forms/uploads/php/files/a2ab922d5b76dd7f38a65aa65125a08d/kefonemodi.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613e95b2d42ef---kasinefater.pdfIn PDF document text
    • https://www.shropshirefurniture.co.uk/admin/ckfinder/userfiles/files/59097289215.pdfIn PDF document text
    • http://flashdisplay.net/UploadFiles/FCKeditor/20210921203406.pdfIn PDF document text
    • https://estoniapools.com/contents/files/mawizep.pdfIn PDF document text
    • https://gadesign52.com/uploads/files/202109121529356361.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1614137e3cfb3f---2247242750.pdfIn PDF document text
    • http://szm.hu/userfiles/file/wekotelusonebodixatode.pdfIn PDF document text
    • http://mtegl.wsystem.sk/userfiles/files/numaribeto.pdfIn PDF document text
    • https://synersys.fr/contenu/file/1013758202.pdfIn PDF document text
    • http://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202109021702107716.pdfIn PDF document text
    • https://prcomponents.com/ckfinder/userfiles/files/baludonososulununodi.pdfIn PDF document text
    • http://j1ent.com/userfiles/file/20211001035517.pdfIn PDF document text
    • https://cissud.com/uploads/ck_editor/files/18738396562.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_off0000b46b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB46B 15944 bytes
SHA-256: 912842aa132c14bd18833fdd4e290115830408949cd972d676fe70a061f6e5db
font_01_sfnt_off0000dce9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCE9 10816 bytes
SHA-256: a9f003cd866713d4d49989e23cb579a85c78c4551e8d1d776aa9ab60285e3209
font_02_sfnt_off0000f5c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5C3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1