Malicious PDF — malware analysis report

Static analysis result for SHA-256 1538b4e22f54390f…

MALICIOUS

PDF

86.8 KB Created: 2021-06-28 07:47:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 05fd40fdc1ab46e7ac7c9ed2e016b4e2 SHA-1: f9a48097508f284a49ef6ca978a274d4a4888c6d SHA-256: 1538b4e22f54390f520c0f24eb6852ac12e427fca052f9cc3041b5f635d2874c
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Numerous heuristics fired, including PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM, pointing to a link farm hosted on compromised WordPress sites. The embedded URLs suggest the document is designed to redirect users to potentially malicious content, aligning with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

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 http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608eb3f4d0014---73020194549.pdf In PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160bed31a5e0ed---mewosuzazimizuvu.pdfIn PDF document text
    • https://gtselect.fr/ckfinder/userfiles/files/10261489389.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609a41327fe69---79128159450.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609085d3ef864---27995084086.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608b5d6ca29e7---pimexibekupopokoluk.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afcc2b14008---24992834571.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca3ccefbc9---kamibukevopew.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a64c9eee8d6---54117865051.pdfIn PDF document text
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/6b8497db38884cf952fdb4a31f8f92d5/wululujepopejojates.pdfIn PDF document text
    • http://asea-admin.com/_userfiles/file/20210501173346.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/9178207722.pdfIn PDF document text
    • https://alshaabcoop.com/userfiles/file/6125730565.pdfIn PDF document text
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a11754eadc4---45482013967.pdfIn PDF document text
    • http://www.makattakasinti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d61a85c694---69383124124.pdfIn PDF document text
    • http://sva-jeanroze.com/xmedia/file/xadafawisudubibujerisosi.pdfIn PDF document text
    • http://businessplan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/jodezonure.pdfIn PDF document text
    • http://www.la-rocca.pl/app/webroot/files/files/lalasijagaba.pdfIn PDF document text
    • http://box8websites.com/ckfinder/userfiles/files/lutev.pdfIn PDF document text
    • https://mimpiindah2.com/contents//files/46429570298.pdfIn PDF document text
    • https://eastmanllc.net/ckfinder/userfiles/files/10432040495.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/81531787290.pdfIn PDF document text
    • http://archerelectricsupply.com/userfiles/file/519009962.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/160804e18f1529---14905372545.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160854d9d39f4f---pedavorafuvalabulized.pdfIn PDF document text
    • http://www.goldenlantern.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160c2c9f654e04---kevojidefulilusa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=how+animals+eat+their+food+videoPDF 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_off0000efc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFC5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000107d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107D7 17348 bytes
SHA-256: 5c495538d5e9b9db42720039fcef7adeeb11f7b20a90ff23fb60004dd1e5166c
font_02_sfnt_off00013532.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13532 10764 bytes
SHA-256: a164ff84dea3a5c44240f4205321cc2ad3350a4c9b7063e5e1e92594091ad8d4