Malicious PDF — malware analysis report

Static analysis result for SHA-256 40f6db3d7d272e28…

MALICIOUS

PDF

74.4 KB Created: 2021-09-17 08:48:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 7bac9f33b9eb512fe864a4a5d794dccd SHA-1: 684e95b28fb2426b64adc5d3a72c341faa23976f SHA-256: 40f6db3d7d272e28c806131ed9239eb3b833cb0ca06e90fb5ca5c736de1b59d2
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to compromised WordPress upload directories, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. No scripts were extracted, and the document body was unreadable, so the rationale is based on the URL heuristics and the overall structure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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 https://newfrio.com/userfiles/files/lawiwopufavoredax.pdf In PDF document text
    • http://psn-monolit.ru/img_file/files/tenebigalatiwege.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/49d1a981ba5dc568b4960ad391915449/87944739005.pdfIn PDF document text
    • http://sanraimundo.cl/dyn/uploads/file/tazenozokaja.pdfIn PDF document text
    • http://okna-stv.ru/userfiles/files/10615652145.pdfIn PDF document text
    • http://wang023spa.com/userfiles/202109file/2021090904054770554.pdfIn PDF document text
    • http://circolonauticofavignana.it/userfiles/files/luxapumurakuf.pdfIn PDF document text
    • http://osteriadelcampanile.com/userfiles/files/pozuxigobu.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fd95db089d---zasiz.pdfIn PDF document text
    • https://sukienmiennam.com/userupload/files/83708626540.pdfIn PDF document text
    • http://aallergy.friend-match.com/upload/files/bukidotatadosulutu.pdfIn PDF document text
    • http://transbur.ru/admin/ckfinder/userfiles/files/43263359502.pdfIn PDF document text
    • http://tmacfashion.com/ckfinder/userfiles/files/giwafesix.pdfIn PDF document text
    • http://9262895.ru/ckfinder/userfiles/files/65713814726.pdfIn PDF document text
    • https://livre-d-art.com/ckfinder/userfiles/files/wepadukitisud.pdfIn PDF document text
    • http://ducthanhtam.com/uploads/userfiles/file/11876110415.pdfIn PDF document text
    • https://securitydm.net/slicice/file/nagetavaxa.pdfIn PDF document text
    • https://olivier-daulte.com/ckfinder/userfiles/files/vexinenarare.pdfIn PDF document text
    • https://beautyyaurient.com/editor_upload/file/kujekosezadiris.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a32f28e276---baxas.pdfIn PDF document text
    • http://jr-bang.com/uploadfiles/20210912213815.pdfIn PDF document text
    • https://subded.org/userfiles/file/28577267538.pdfIn PDF document text
    • https://premiersuli.hu/files/files/wiwexa.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139e98a7996a---20221243609.pdfIn PDF document text
    • http://ansing.nl/userfiles/file/vijejisikatonikewobofupi.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613716cd6dc01---mojerikugar.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=3d+plan+creatorPDF 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_off0000c007.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC007 17072 bytes
SHA-256: 9632c39ef3dee79d3477a94cc53bf2332c29af4e3b4bc36dfef19c927dade457
font_01_sfnt_off0000ec37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC37 10320 bytes
SHA-256: 1a5ae10561c61a79401bf7a2530ea563bc58529c84e0ea1abd11818dc4a73ca4
font_02_sfnt_off0001039b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1039B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1