Malicious PDF — malware analysis report

Static analysis result for SHA-256 984b9b441e9f1694…

MALICIOUS

PDF

95.1 KB Created: 2021-09-18 06:34:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: fc7588226f31bcf51062c6f8f070d319 SHA-1: 64441cde62c68ee5e8b3185e4314af2a2446a80f SHA-256: 984b9b441e9f169425f43705a6009c2b25edea256905e73e3b5aef876d76bc17
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many hosted on compromised CMS uploads or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the links and the heuristic firings point towards a malicious document, potentially leveraging embedded JavaScript for redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://www.mds-horizons.com/upload/files/tomutuko.pdf In PDF document text
    • http://izeninfo.net/admin/upload/files/xuvon.pdfIn PDF document text
    • http://siamsnail.com/media/userfiles/files/waporudapemisozubar.pdfIn PDF document text
    • https://doina.md/fckeditorfiles/file/jerosumazakidax.pdfIn PDF document text
    • https://renebeumer.nl/userfiles/file/guxunidiwo.pdfIn PDF document text
    • https://foodphotoshop.com/userfiles/files/64085299356.pdfIn PDF document text
    • https://supermagnum-bg.com/ckfinder/userfiles/files/80939018391.pdfIn PDF document text
    • https://jackyrouxmethode.com/userfiles/file/29352741752.pdfIn PDF document text
    • https://serrechevalier-skifun.com/imagesfile/82082745420.pdfIn PDF document text
    • https://www.agencesramos.com/ckfinder/userfiles/files/61382179951.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16138da22177bc---41374418312.pdfIn PDF document text
    • http://baodieptailor.com/uploads/2021-09-12/images/files/75822890629.pdfIn PDF document text
    • https://motty-etai-sharon.com/files/files/faraxipifepimoxejufex.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/161357eb6460ba---sujok.pdfIn PDF document text
    • http://sten.kr/club/data/userfiles/file/20210902160015.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1613a3fdb92e4f---pebusulidapan.pdfIn PDF document text
    • http://qishuochem.com/siicea/userfiles/file/mibofusorukunobedarowal.pdfIn PDF document text
    • https://cauthinh.com/luutru/files/317841953.pdfIn PDF document text
    • http://air-con.ru/upload/files/tobefad.pdfIn PDF document text
    • http://topflexsports.com/uploads/33972574471.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/161305efb646d8---fimagolevegedafowaparuru.pdfIn PDF document text
    • https://picinterior.com/ckfinder/userfiles/files/jekataxilakoziduxa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=use+two+apps+at+once+androidPDF 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_off000110a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110A3 10552 bytes
SHA-256: 15b869e0af6891b20a4eb99700d82ef473a9774ccf6808a38dd01240dbc5302e
font_01_sfnt_off000128e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128E2 17472 bytes
SHA-256: fcc83521a88d7936d80fd8626710e4d511b9042e6efff25e18112fac97b26fb3
font_02_sfnt_off000156e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156E8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1