Malicious PDF — malware analysis report

Static analysis result for SHA-256 88b184a5ecce214b…

MALICIOUS

PDF

72.4 KB Created: 2021-09-26 20:06:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: c30403012f2de43dda6b4705f947f404 SHA-1: cf3fb6b5b8029c306bd4e6ea5f27ad09f272e42e SHA-256: 88b184a5ecce214b15e4ab10d3597580ea373caec6f12bee0b57dcb4b3673e77
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external links, many pointing to compromised CMS uploads, suggesting it's designed to lead users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm nature are indicative of a phishing or malware distribution lure, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://pistant.ru/uplcv?utm_term=hook+up+apk PDF link annotation
    • https://2ruoteexpo.it/ckfinder/userfiles/files/xadaneworapizomasopotedon.pdfIn PDF document text
    • http://libron.pl/fckupload/assets/file/jukumuwewono.pdfIn PDF document text
    • http://domgr11.ru/uploads/files/lalonukumarujefunedixadap.pdfIn PDF document text
    • https://marathonroller.com/userfiles/files/xovubewofag.pdfIn PDF document text
    • http://w-w.cn/isee/pfm/cms/uploadfile/fck/file/72139512795.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16146f0217c406---13021691450.pdfIn PDF document text
    • https://topupdana.com/contents/files/renimuxo.pdfIn PDF document text
    • https://yodishit.com/uploads/userfiles/file/dibokarirusal.pdfIn PDF document text
    • http://yogathoitrang.com/quangbasanpham/app/webroot/upload/image/files/27245324895.pdfIn PDF document text
    • https://westhygiene.hu/editor_up/venigefuganomoxubu.pdfIn PDF document text
    • http://gramercygrand.ru/files/file/gexusezusurana.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140bf63023a4---gidotiledapulemifo.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ede2c18e70---2472051669.pdfIn PDF document text
    • http://isdoor.ru/uploads/files/wavakijajakalorozupir.pdfIn PDF document text
    • http://hangquangauto.com/files/72109290385.pdfIn PDF document text
    • http://finemetal-cn.com/upload/files/18319630998.pdfIn PDF document text
    • http://findingthegrey.com/userfiles/file/fonamivedi.pdfIn PDF document text
    • https://dptech.vn/uploads/files/94670382875.pdfIn PDF document text
    • https://somogyplusz.hu/files/naturadikuvefomafavero.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/famomidusejapumo.pdfIn PDF document text
    • http://gpszone.hu/upload/userfiles/file/vuzifikoguser.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/50d473ba10567623e9c2e72b0fdc478e/36956957286.pdfIn PDF document text
    • http://limuzine.md/userfiles/file/guboj.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_off0000b675.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB675 18056 bytes
SHA-256: 050d7cc48c73f3e9a81215243ff366d00d00c156d2192cf3cb40ddbbcf51806d
font_01_sfnt_off0000e55e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE55E 9688 bytes
SHA-256: 77eb444a90ebdbd572a31892e86b9c1587902794e4e2f2f8f84b84a0e513358f
font_02_sfnt_off0000fa85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA85 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1