Malicious PDF — malware analysis report

Static analysis result for SHA-256 c44eaa183ed7be03…

MALICIOUS

PDF

89.6 KB Created: 2021-06-30 15:50:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 18cc76ca769ed8d0622c648ada402c1d SHA-1: 866f3a96265c1b8d7e55140a906020bd8cf5d261 SHA-256: c44eaa183ed7be03886fdab515b7c4b033c10aa48ad3797149b8626a9ff2d7b0
96 Risk Score

Malware Insights

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

The PDF document contains a link farm, with many URLs pointing to external websites. Several of these URLs are hosted on compromised WordPress sites, indicating a potential distribution or hosting mechanism for malicious content. The ML classifier also flagged this PDF as malicious with high confidence.

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://castilloexterior.org/ckfinder/userfiles/files/naxelowel.pdf In PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/16079fb4645ac8---deluraxexuja.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/c8kj82vnant28rib0b8q51tp3t/lowinebimugapu.pdfIn PDF document text
    • https://allmassage.net/upload/file/20210520112404.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/16082a380954c5---wobatateviziwanafezibato.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/160af7dbb6709e---7553625985.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609ad6621e224---sugofo.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8bd37a483e---legusa.pdfIn PDF document text
    • http://cuhs1981.com/clients/8/82/82ca37c076ec4232796cb58ed009bb3a/File/80278238050.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16077fd7c2b7a4---xeviziloz.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608802757e6db---nusenozug.pdfIn PDF document text
    • http://a2itsolutions.com/chop/multimedia/userfiles/file/gujog.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a0c6c29602---tixiluvopuxuzefi.pdfIn PDF document text
    • https://livre-art.com/ckfinder/userfiles/files/kufadimi.pdfIn PDF document text
    • https://ringid.vn/ckfinder/userfiles/files/82919649560.pdfIn PDF document text
    • https://harrisitalia.it/uploads/file/bumimoseniterut.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/16085b2d4ea78c---zevatobenatibef.pdfIn PDF document text
    • http://w-f-l.de/user_img/file/bevozegaguvukupojuxeze.pdfIn PDF document text
    • https://cal.lighting/wp-content/plugins/super-forms/uploads/php/files/ca571404734c94027b2a5ce19560b857/dopezoda.pdfIn PDF document text
    • http://proxima-design.cz/files/file/sevamekulebawolimitawug.pdfIn PDF document text
    • https://www.ideaklinikankara.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f2ce0baddd---mogonijuvetev.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077746d07e3e---22137774761.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1b4ec1b56e---kopor.pdfIn PDF document text
    • https://eventaipei.com/upload/files/69641585722.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=goulash+with+noodlesPDF 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_off0000fab8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAB8 17728 bytes
SHA-256: 24611f6912e1485843d6c2b0de3ae25f3cc36e432071a39d56e7de2e6b58af09
font_01_sfnt_off00012941.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12941 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014158.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14158 10468 bytes
SHA-256: b8aa78cb85fc6a5c938c23ccab318e553c02c9b0c2f480ea32e90573ac887505