Malicious PDF — malware analysis report

Static analysis result for SHA-256 a66e8546be0b6617…

MALICIOUS

PDF

78.9 KB Created: 2021-09-08 07:23:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d6fffeb03e894bd5eff7856e31c2b560 SHA-1: 3b780afcbb1dab54f46910dd4fc3041d9d3122cd SHA-256: a66e8546be0b66174eca16157d05399310578a77202048e9dce218e24b9bbe19
104 Risk Score

Malware Insights

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

The ML classifier strongly indicated maliciousness, supported by heuristics identifying the PDF as a link farm hosted on compromised WordPress sites. Many of the extracted URLs point to potentially malicious PDF files, suggesting a redirection or download attempt. The document body is heavily obfuscated and unreadable, providing no further context.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d66badb899---78363597773.pdf In PDF document text
    • http://kledingindex.nl/images/uploads/nifagemipesaguz.pdfIn PDF document text
    • http://dycelife.com/userfiles/file/3243437622.pdfIn PDF document text
    • http://xn----7sbev0bhje.xn--p1ai/images/news/file/32868595203.pdfIn PDF document text
    • http://apsencollege.org/test/fckeditor/file/94409312059.pdfIn PDF document text
    • https://www.charroninc.com/wp-content/plugins/super-forms/uploads/php/files/67f66495cb6b58023c863b5d2b15bc6e/tibixuj.pdfIn PDF document text
    • https://greyquotient.com/wp-content/plugins/super-forms/uploads/php/files/c6ff50ad0d902f2593211b9d0a9f095e/20705135127.pdfIn PDF document text
    • https://aedwea.com/upload/foto/11470698798.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160888f04422b5---60086332688.pdfIn PDF document text
    • http://aite-materials.com/upfiles/file/2226802141.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606f29363617e---teditavedumuwirebujogaxud.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160b062e004cd2---43479156469.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0bc0f40d00---lifedibozulorulodepog.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612944b7b3b40---guvukekerur.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/dnga9l6gvdhracntoffhricp2i/52963123372.pdfIn PDF document text
    • http://eichler-kammerer.de/62416403350.pdfIn PDF document text
    • http://carsonpokebar.com/uploads/files/15936108490.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/6de4d54a8cd44a60dd7026391ba523a3/6380093245.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160c9d68e9b94e---69066440843.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/f59acb8052bdd933da1a78c52210305a/netepiliju.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/0m4g91epkrco7hvq3q7tme2mkm/64994300940.pdfIn PDF document text
    • http://deasreunion.com/clients/860224/File/24045795224.pdfIn PDF document text
    • http://southerncross-ex.com/images/blog/file/wesuxinusese.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/005dfa94802abb874ee3f1c6e960c045/ruvojimirazadiwow.pdfIn PDF document text
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16082ee26f37db---dajulu.pdfIn PDF document text
    • https://99shayari.in/userfiles/files/saminofuvujipasodazogivip.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=inequality+questions+and+solutions+pdfPDF 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_off0000c817.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC817 20008 bytes
SHA-256: 66536b076f47915d554f7e13b1e96990d91362fba7c8687ae3f5a4e26dab1f01
font_01_sfnt_off0000fd3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD3C 10700 bytes
SHA-256: 2385b5acfb2bb0c608ca9b4e5963064745500a2166c3c72f689115e55f0c71b5
font_02_sfnt_off000115b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115B7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1