Malicious PDF — malware analysis report

Static analysis result for SHA-256 53e663442dd064ca…

MALICIOUS

PDF

133.2 KB Created: 2021-08-16 04:02:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2b9a9a88f261f9d2cb30922272e487c7 SHA-1: 302379292c04839246b6d560b566c69c1f8b64df SHA-256: 53e663442dd064ca8e7e53188a612ef456b3f7a92e6b443df68f79481204f02a
96 Risk Score

Malware Insights

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

The PDF file contains a large number of links pointing to compromised WordPress sites, indicating a link farm designed to obscure the final destination. The ML classifier flagged this PDF as malicious, and the presence of multiple links to potentially malicious content supports this assessment. No scripts were extracted, and the document body was unreadable, so the primary attack vector appears to be the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7639

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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://insights3.com/wp-content/plugins/super-forms/uploads/php/files/eccb503367f95b86bcf4f4e7a3486776/sofifu.pdf
    • http://bloomx.com/sites/all/sites/bloomx.com/files/newofosejexodafimem.pdf
    • https://fatheragneliti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610b578488cb7---49195521784.pdf
    • https://hanyauntuktesting.com/contents//files/rewubusofubi.pdf
    • http://dominopark.pl/public/upload/ckfinder//userfiles/files/91611209576.pdf
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/161154193ee687---rosakulunisuso.pdf
    • https://chupwo.com/editor_upload/file/radilerobadadigajipudugop.pdf
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085078cb0723---25413727912.pdf
    • http://automsystem.com/UploadFile/file/20210504221443954.pdf
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/a8b7a99658e5dd2923aeee8020f30c25/ruzawekodaxeginoweraxoj.pdf
    • http://libertyquad72.fr/userfiles/file/serowigevijujax.pdf
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/2b7c5picdo7asq8vrvm0lngl9l/gapifatovaj.pdf
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5f1af09fe9---pozixobiporu.pdf
    • http://dblbtech.com/userfiles/file/42709009233.pdf
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/160881d562bc59---dezulikokakufuvajonowep.pdf
    • https://1877painters.com/FCKeditor/file/32582523769.pdf
    • http://professional-tuner.at/uploaded/file/26720985729.pdf
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/39af4fa42454fc781a1f48a192189d1f/79660676833.pdf
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160fde2ce038a8---natiwoxire.pdf
    • http://perilatomsk.ru/ckfinder/userfiles/files/nometibefin.pdf
    • https://selapro.com.au/application/third_party/ckfinder/userfiles/files/63266473821.pdf
    • http://faizleathergloves.com/userfiles/files/88098198699.pdf
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160fd8fe11da87---55200238051.pdf
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/e6f7f33b2d8415a80fd03b01e9097ae5/41073171803.pdf
    • http://sam-global.ch/files/file/jowizerelanowewef.pdf
    • http://abcbyspu.com/ckfinder/images_store/files/livefuwu.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=what+is+amperometry
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001b1cb.bin
b8c579a3c93d49151f9fee022fab4b869bbd15f48df957d43cdb725983e6879b
pdf-font-stream PDF embedded font (sfnt) at offset 0x1B1CB 19564 bytes
font_01_sfnt_off0001e502.bin
273231fe66af1aab6a52f9bccd3576a4c307ef240bffd7d5e1ec5f7aebe014c7
pdf-font-stream PDF embedded font (sfnt) at offset 0x1E502 10476 bytes
font_02_sfnt_off0001fce3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1FCE3 16792 bytes