Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f73e7e2ec4864ed…

MALICIOUS

PDF

90.3 KB Created: 2021-07-06 02:49:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c3fba3da61c69ca81e2c38f5edc7903c SHA-1: 77a9b2dc88d46f6643feaf5d01c6e579aec328f4 SHA-256: 3f73e7e2ec4864edcfe4fda2fd634ed6f2e129e32efa9852cc8e383cf74981fe
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous distinct hosts, many of which appear to be compromised WordPress sites. The ML classifier strongly indicated maliciousness, and the structure suggests an attempt to manipulate search engine rankings or distribute further malicious content through these compromised sites. No scripts were extracted, limiting the analysis to the document structure and embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 5

  • 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://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/131400e4fcd15373c0cb1d1b3e186243/24110566158.pdf In PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608309e97c2f2---20281405827.pdfIn PDF document text
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/65e2f8a9a04a591afa71f91d560f97f1/98926090991.pdfIn PDF document text
    • https://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/70a8483b76c38c3d3f716034949beb27/siserove.pdfIn PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bd1cee8919---26341273832.pdfIn PDF document text
    • https://cissud.com/uploads/ck_editor/files/4634953696.pdfIn PDF document text
    • https://www.federatedlighting.com/wp-content/plugins/super-forms/uploads/php/files/954a888094ec03dd9ed5ec36e1606c29/4065420942.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2849aabdaf---gamevoxejobo.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aca7564ae59---tezexo.pdfIn PDF document text
    • https://sgdivorcelawyers.com/wp-content/plugins/super-forms/uploads/php/files/f2fffb6f645ce19ad8d478064d8287f5/58159396143.pdfIn PDF document text
    • http://dragonera.cn/admin/userfiles/file/46285678253.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b2ce2b6cf22---bamuwivarol.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bb53f210883---87104872006.pdfIn PDF document text
    • http://caycanhtuyhien.com/uploads/image/files/84859645857.pdfIn PDF document text
    • http://mfahk.com/upload/files/30175872863.pdfIn PDF document text
    • http://studiosimonepantaleo.it/userfiles/files/21998827916.pdfIn PDF document text
    • http://raiders71.com/clients/4/41/4134020f2f298c111575624a380fabfc/File/83089671718.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c138212022b---ladogasafeduliji.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3deb9e7e02---29030715485.pdfIn PDF document text
    • http://humanitool.ru/userfiles/file/22537960660.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/6ua4gjt4mtvq9784f6ntvbnbc3/bimiretosumip.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cd0c04aa371---20708649679.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/8442a5aac64293c812d34870bb0bca11/14171469773.pdfIn PDF document text
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/kdpm5saoojh6qht1iek5v6oe9a/80526209454.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607e669035f8c---24757568575.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=polio+and+vaccinesPDF 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_off0000fdf4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDF4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001160b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1160B 10232 bytes
SHA-256: 943074fbf687003896d79e78f62aa5bdc981ff8446d6dac90f4c5a5057353c9c
font_02_sfnt_off00012d1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D1E 17772 bytes
SHA-256: c7ca5ea8aecd5231f570001fed09ddc94e1a95810f77bef5c5c1cd0a58a80aa9