Malicious PDF — malware analysis report

Static analysis result for SHA-256 04c7143a3cb9df79…

MALICIOUS

PDF

74.2 KB Created: 2021-09-13 04:19:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d94c1dd2a9090b703222dce14aa53b77 SHA-1: e686be7bb85995f2a139f4fc075def0041adf082 SHA-256: 04c7143a3cb9df792c82b9ed2b15f7600c4b3dff70366690f67aa43c8b86042e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to external PDF files, suggesting a link farm or redirection mechanism. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags the use of disposable hosting and redirector patterns, common in phishing and malware distribution campaigns. While no scripts were explicitly extracted, the PDF structure itself is being leveraged to redirect users, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://mangallagn.com/images/file/fojazumomaxoz.pdf In PDF document text
    • http://awards.nl/img/cms/file/vazipesedarezewupu.pdfIn PDF document text
    • https://k-barrierfree.com/FileData/ckfinder/files/20210912_87B4F314EB69C020.pdfIn PDF document text
    • http://liavanhaeringen.nl/userfiles/files/nifesebabifa.pdfIn PDF document text
    • http://archiwum.wyryki.eu/admin/ckfinder/userfiles/files/vupoginutimixuriva.pdfIn PDF document text
    • http://srividyaastrology.com/userfiles/file/65912876819.pdfIn PDF document text
    • http://bpabv.nl/uploadfiles/file/10989857939.pdfIn PDF document text
    • https://www.bussmann-tiefbau.de/ckfinder/userfiles/files/baravazamobivek.pdfIn PDF document text
    • http://gelateriacool.it/userfiles/files/8419952120.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613c21802cf9c---42157014361.pdfIn PDF document text
    • http://xn----gtbercbfedtm3b.xn--p1ai/admin/ckfinder/userfiles/files/35396527519.pdfIn PDF document text
    • https://kamarkosong.com/contents/files/ridisuvefa.pdfIn PDF document text
    • https://hotnewsmd.deca.md/upload/userfiles/files/59577200927.pdfIn PDF document text
    • http://soles2walk.com/data/file/7848452867.pdfIn PDF document text
    • https://jnvhardoi.org/ckfinder/userfiles/files/99086879256.pdfIn PDF document text
    • https://samirkumarpaul.com/ckfinder/userfiles/files/zewewonobevewibo.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1613a83167b05a---26702841436.pdfIn PDF document text
    • https://global-brand.net/userfiles/files/83687456165.pdfIn PDF document text
    • http://goldenstarhotel.vn/images/uploads/files/6110034674.pdfIn PDF document text
    • https://millvalley.com/wysiwygfiles/file/42497800830.pdfIn PDF document text
    • http://elateridae.com/images/FCKeditor/file/3928227777.pdfIn PDF document text
    • http://luchetti.it/userfiles/files/34907745639.pdfIn PDF document text
    • http://partnerplus30.ru/images/fornews/files/folebidiwiditabujijo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=z+launcher+apkPDF 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_off0000c239.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC239 10148 bytes
SHA-256: 281ecd7b58dc5912f7751df9f8f0edc07667779ae115dd564feb3fa5e4f762fd
font_01_sfnt_off0000d8d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f0e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E3 16480 bytes
SHA-256: 38636466e99bbd0484879a5005b8b5fb43f05c739340718097f69e6713484b79