Malicious PDF — malware analysis report

Static analysis result for SHA-256 3dc4d7623eea1270…

MALICIOUS

PDF

91.8 KB Created: 2021-04-29 04:00:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 438fe3fd4d5d55fe9e41232be022c27b SHA-1: 51aa10f5ab8f2c986736f9320b098f8b045825b7 SHA-256: 3dc4d7623eea12700f321ea25c52aa0b94567ae9d713c21f091118d473135d14
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous links pointing to compromised WordPress sites, suggesting it's part of a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and contains metadata indicating it was generated by wkhtmltopdf, a tool often used to create malicious PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/160715bf37431c---77122998933.pdf In PDF document text
    • http://miamiwars.pl/wp-content/plugins/super-forms/uploads/php/files/9637aca12f73d49ec709f6b589dd74e7/87773058266.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/2ee900c7ecd9a81dc14bdd4dc100efa7/72688902022.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/94756922dc78f2d3de9f3e36edcb30b1/dejatavepomojezonukusopaz.pdfIn PDF document text
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607e9f1484883---wutopagatakif.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5c746b2f5---81493428490.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/16071b9de888a0---16145355573.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/97ab34c018d4d8454cc9f8e192b61f49/64684343279.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/d65a8b8502f73c0023b9f34fe5eceb75/kenozepizi.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d179761c76---nopaxodosifu.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607200395eede---ralosipepuneviweken.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/1dbd3bc2694fabf571602d45866ba6d5/93250467568.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/kivhmief55i3d3d5dadae859gj/23098695667.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/0sb72g7kpgc5ppc5k77fin4n3u/gekorovoju.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/160896cdf2f54d---tamumumovatifilapevesem.pdfIn PDF document text
    • https://jclifeschools.org/wp-content/plugins/super-forms/uploads/php/files/1e9496d96229c56771c978a60d58b4b2/vamosubonuwur.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076df777f07c---16783454662.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=amethyst+rust+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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000112a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112A5 5008 bytes
SHA-256: 80e41e5de284d9b6fa0d6047df2abd4d86160fcf5143b921201c30183c89b739
font_01_sfnt_off00012379.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12379 1824 bytes
SHA-256: 604506df234ced92337ae1b2d061d1ec0a533c526572764e580229214873e279
font_02_sfnt_off00012c67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C67 11552 bytes
SHA-256: fff02f8d1aaf1b90c7297df4572bb26aaae13c602cfa74ea667b0f083ef90d7d
font_03_sfnt_off0001535f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1535F 4324 bytes
SHA-256: ce7e2e230a41ba6fc2d7d2240890c8289d67876d84a3d076d67c0b48111c8230

Open this report in the interactive analyzer, or submit your own file for analysis.