Malicious PDF — malware analysis report

Static analysis result for SHA-256 650aaa623548bf8c…

MALICIOUS

PDF

77.3 KB Created: 2021-09-07 17:48:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 0366f3c15c08f6405955d5d1a3cd3ca8 SHA-1: b21bf2495bc6c75920693bc71b3b589d8e2db362 SHA-256: 650aaa623548bf8c870e6f0186b8214c22f0e50cc472c7f0c7036d36a1ae7bd8
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm. The ML classifier strongly suggests maliciousness. While no scripts were extracted, the structure and URL patterns are consistent with SEO spam or a lure for malicious content delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://www.icslights.com/wp-content/plugins/super-forms/uploads/php/files/15cb4ac26638a24b47259e390f905adb/19547481736.pdf In PDF document text
    • https://istanbulbalbir.com/upload/ckfinder/files/zalebekabuxizeg.pdfIn PDF document text
    • https://rinducm1.com/contents//files/75704760447.pdfIn PDF document text
    • http://color-gateway.com/userfiles/file/35769528704.pdfIn PDF document text
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a28aa069114---64814806360.pdfIn PDF document text
    • http://whipitleather.com/userfiles/file/14840336578.pdfIn PDF document text
    • http://systemsbiology.at/uploads/assets/file/zelalemamimobokexinar.pdfIn PDF document text
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/1610e56b1afc43---57002728864.pdfIn PDF document text
    • http://fobosgrunt.ru/files/ckfinder/files/1670224772.pdfIn PDF document text
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/eba68b52003dcd4badadc2256d503a1c/zigivobesofiwuz.pdfIn PDF document text
    • https://bhalakusari.com/uploaded/ckeditors/files/geboga.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1c6101605c---55433649938.pdfIn PDF document text
    • http://sjar-tech.com/uploadfile/file///2021051700153774.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e50e0bbb3fa---34172164250.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfbc3406077---tukebafowaju.pdfIn PDF document text
    • http://24cvety.ru/upload/files/pelikuxizojis.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/k0hu1fhk6e0j8cmrgmro53thks/kokaribage.pdfIn PDF document text
    • https://triangle-electronics.com/assets/userfiles/file/49153519970.pdfIn PDF document text
    • http://vicorsupply.com/uploads/images//files/wipijawojojutak.pdfIn PDF document text
    • http://cocoon-source-harmonie.fr/public/file/motodozavafakowulelolaxa.pdfIn PDF document text
    • http://janjoling.com/public/ckfinder/userfiles/files/43920973901.pdfIn PDF document text
    • https://sushixusa.com/userfiles/files/bejuwarid.pdfIn PDF document text
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089a3777eb65---29865866999.pdfIn PDF document text
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/d102da201bd0ecc8820cb747ec8cec9d/xoxogel.pdfIn PDF document text
    • http://studiogallerani.it/userfiles/files/20690716306.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=mpsc+blank+answer+sheet+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_off0000c6c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6C0 10816 bytes
SHA-256: 5c197902f3e6e11794f5d0a8e73eeb2d5df03a2a4fa8b7db60afba4a90bf5f02
font_01_sfnt_off0000df8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF8E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f7a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7A0 18352 bytes
SHA-256: 4cf123830b5f77bc2b16feb98e4da9e69dd334e5b3d824364fa343343b6a67ae