Malicious PDF — malware analysis report

Static analysis result for SHA-256 12728dd8c61a925e…

MALICIOUS

PDF

70.1 KB Created: 2021-10-01 12:52:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 091bea0734606e215da2cb3486aaca15 SHA-1: c3588bcd00aa2155ccd7362462ba98fdc371636d SHA-256: 12728dd8c61a925ef6a8592224bf501bf921d268f9a72c90545fccf444bf12a2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised or disposable domains, indicating a link farm designed to redirect users to potentially malicious content. Heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly suggest this malicious intent. The ML classifier and ClamAV detection further confirm the malicious nature of the PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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=cm+17+mod+apk PDF link annotation
    • https://almuhja.net/ckfinder/userfiles/files/41006573042.pdfIn PDF document text
    • http://vvk-wiedermann.at/userfiles/file/gimivirariwazebirimebagud.pdfIn PDF document text
    • http://abwcrainhwy.com/uploads/files/nofaruzibatemubaxorawuwo.pdfIn PDF document text
    • http://nanumed.ro/uploads/files/56536032008.pdfIn PDF document text
    • http://crm333.com/documentos/file/10232468391.pdfIn PDF document text
    • https://sankaibearing.com/userfiles/files/76798319004.pdfIn PDF document text
    • http://centrons.com/uploaded/file/14071944576147850f8d9c7.pdfIn PDF document text
    • http://elliptical-trainers.ru/ckfinder/userfiles/files/38457778450.pdfIn PDF document text
    • https://onderdurdu.com/upload/ckfinder/files/susigolazabekojobipaw.pdfIn PDF document text
    • http://morebricks.com/ckfinder/userfiles/files/neloronafuju.pdfIn PDF document text
    • http://fuzoku-kyujin.jp/ckfinder/userfiles/files/nemudulu.pdfIn PDF document text
    • http://sabaispa.net/userfiles/file/genidimexarafalitovaporan.pdfIn PDF document text
    • https://cowichanseniors.ca/userfiles/file/bulesowowuvo.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/161431465a0bf7---54625425124.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/161559d7e455d8---futalatifikiroruvapofa.pdfIn PDF document text
    • https://ost-fogging.com/upload/files/16554046090.pdfIn PDF document text
    • http://thicongdiennuocmiennam.com/uploads/files/60386694897.pdfIn PDF document text
    • http://connect-event.fr/ckfinder/userfiles/files/96632750749.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613630f32ed65---ziguwoveroxafulovolez.pdfIn PDF document text
    • http://serenetour.com/image/upload/File/bejata.pdfIn PDF document text
    • https://www.larche-de-jules.fr/ckfinder/userfiles/files/97336780596.pdfIn PDF document text
    • http://perksys.com/userfiles/file/dizisokanovolonibabakono.pdfIn PDF document text
    • http://mvdeastudio.it/userfiles/files/menubin.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_off0000b00b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB00B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c81d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC81D 17448 bytes
SHA-256: ce7218e6c447b2de7ca18605171f38baa03eb4f03aa5c126e333015aa8580dbc
font_02_sfnt_off0000f4fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4FC 10036 bytes
SHA-256: a604214d5846ad94dffd045ccf94082a60bb1076252403512b511974dc2ffaa3