Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6c7831709fceea1…

MALICIOUS

PDF

80.1 KB Created: 2021-09-14 01:30:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8898976a19819b6a60dd38044a07336d SHA-1: 7c711c92ceff9245770a3eda54c538428e9d80a9 SHA-256: c6c7831709fceea15d4bd280d21aedf4651a77677a769ad013fa9befef33f1fb
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which point to compromised CMS upload storage or are part of a link farm on disposable hosting, indicating a phishing or SEO poisoning attempt. The document body is heavily obfuscated, preventing analysis of its specific content, but the presence of these links strongly suggests a malicious intent to redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 http://guides2alpes.org/uploads/file/linuwufekasolobidivozufat.pdf In PDF document text
    • http://szjwwj.com/userfiles/file///wazizoporafavodesetuser.pdfIn PDF document text
    • http://jingluo.net/uploadfiles/files/xemefarotisoti.pdfIn PDF document text
    • https://www.mmgrowersg.com/ckfinder/userfiles/files/zapewelab.pdfIn PDF document text
    • http://woori-tour.kr/FileData/ckfinder/files/20210913_70FFEE059D9CF509.pdfIn PDF document text
    • https://siangyun.com/upfiles/editor/files/29677370863.pdfIn PDF document text
    • http://ellev.fr/upload/files/43701204595.pdfIn PDF document text
    • http://dush-kz.ru/uploads/fck/file/215433323.pdfIn PDF document text
    • https://augsburger-dartliga.de/uploads/file/23405221075.pdfIn PDF document text
    • http://fuhua.tumujike.com/assets/upload/files/202109140257278360.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130ee2a101d6---20906682257.pdfIn PDF document text
    • http://abdon.madteam.net/ckfinder/userfiles/files/nojune.pdfIn PDF document text
    • https://cylinder96.ru/admin/ckfinder/userfiles/files/97169867546.pdfIn PDF document text
    • https://ka-base.no/images_students/files/gunujaxefugoziremajos.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/161333d8bb4163---fafumikufibujotisob.pdfIn PDF document text
    • https://smartbrand.ro/mm/file/51919122307.pdfIn PDF document text
    • http://castudio.eu/userfiles/files/15152435574.pdfIn PDF document text
    • https://profitaler.com/UserFiles/file/wexagamajevifogutamo.pdfIn PDF document text
    • http://goodtraefarm.com/ckupload/files/62688966746.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/16130bba3044f7---xefozenanumebuxe.pdfIn PDF document text
    • http://leaders-adv.net/userfiles/file/63457746551.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=cheeki+breeki+roblox+idPDF link annotation
    • http://louisiana-arts.org.s150269.gridserver.com/siteuploads/editorimg/file/22954164513.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_off0000d05d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD05D 19664 bytes
SHA-256: 07b079ebe161329289e966bc72e2c05a506268e2a92db8f8d801f6c43b20ba98
font_01_sfnt_off00010404.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10404 10176 bytes
SHA-256: 9fc9129bef52da6cec059289200e3453ac42b71156119ad4981d189de9e7bdac
font_02_sfnt_off00011ae1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AE1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1