Malicious PDF — malware analysis report

Static analysis result for SHA-256 73d098b13d6c941f…

MALICIOUS

PDF

74.9 KB Created: 2021-06-30 16:29:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 89bc641cefba9d74395a971ba2658e85 SHA-1: f0af460ac0be8874a5f624bb39ac3f622385cb2f SHA-256: 73d098b13d6c941fd006beb300e1d46ce16c816ce793ee50aa5b9638cc136c26
96 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to compromised WordPress sites, likely intended to manipulate search engine results or distribute malware. The ML classifier strongly indicated maliciousness, and the structure suggests it's part of a larger campaign to redirect users to potentially harmful content. No scripts were extracted, but the PDF structure itself is the attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/160c5e2c4d196a---jisileranarosojabis.pdf In PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093f3b357fc8---6658522921.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/91fca1f8c9c7d3b00d8a4922a911cea0/70967557841.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/51183d66253727547c9b748d16831a92/pelabini.pdfIn PDF document text
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/b8a9e15b966db0ba6967ed66f5e7bb4f/49586783482.pdfIn PDF document text
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/85577307783c6febad8c516128d3a519/sixulozejekubedoxulule.pdfIn PDF document text
    • https://goldenparadisestsimons.com/wp-content/plugins/super-forms/uploads/php/files/0f878a2942b13bad0c86f8a91beab259/38117714314.pdfIn PDF document text
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/3f9d34a6a09de6e1ce89f9e833170fed/bezijufawilevuvoz.pdfIn PDF document text
    • https://lacecinella.com/writable/public/userfiles/file/pigitajebos.pdfIn PDF document text
    • http://cimkezes.hu/uploads/ckfinder/userfiles/files/7066541652.pdfIn PDF document text
    • http://pathtojanna.com/userfiles/files/dimatape.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070b186f2584---2730564640.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160768a1bc700b---fimiv.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/160972b4b5ce31---53911900108.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070f1e250545---sexavigaveve.pdfIn PDF document text
    • https://voolabs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adb566382fd---62650983456.pdfIn PDF document text
    • http://alpha-cp.com/userfiles/file/dikodorujufajuxubigotun.pdfIn PDF document text
    • http://jyotiacademicpress.org/uploads/file/6082984585.pdfIn PDF document text
    • http://maynenkhiinverter.com/media/ftp/file/tujoxitejilakajajava.pdfIn PDF document text
    • https://ecobox.eng.br/wp-content/plugins/super-forms/uploads/php/files/v7gid79g5ibr5uvrhpb04er898/24795815165.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608181fadd6a6---viwemumurotovokavor.pdfIn PDF document text
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/9efba58353630215bb2e9ebe72c8b551/24774684444.pdfIn PDF document text
    • http://kondicionery-krasnogorsk.ru/upload_picture/file/fufotodipipidi.pdfIn PDF document text
    • https://masini-de-ambalat.ro/images/userfiles/82942332642.pdfIn PDF document text
    • https://ahreco.com/uploads/news_file/63344420478.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=easy+food+ideas+for+lunchPDF 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_off0000c3d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3D3 10672 bytes
SHA-256: d4a1ea9b774778cc5edeff918a2e83e28a491a4b64df01cafbf1d4909befe572
font_01_sfnt_off0000dc2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC2C 16468 bytes
SHA-256: 9e4858d5aab83cbcfa30c88a76c1bf197a46dfaf7d389113b1bd4d261af254a2
font_02_sfnt_off0001062d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1062D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1