Malicious PDF — malware analysis report

Static analysis result for SHA-256 e50ef4b5a3d3b904…

MALICIOUS

PDF

73.7 KB Created: 2021-07-20 13:50:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 65f097b978e57c44866f79b13f85a8c3 SHA-1: d698fee713c2e18f490c5e0f41b6ffd9d6d31a42 SHA-256: e50ef4b5a3d3b90481f0747191630b58b1a686ac1227d85be37ea88798ded3b4
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories, indicating a phishing or distribution lure. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and unreadable, but the presence of a link farm and compromised hosting is sufficient evidence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://maduraigarlandshop.com/userfiles/file/27931712433.pdf
    • http://yourbuilding.ru/userfiles/files/30444946686.pdf
    • https://cplastik.com/data/cms/file/44839471347.pdf
    • http://akkoryazilim.com/userfiles/file/88513490092.pdf
    • https://noriupapildu.lt/ckfinder/userfiles/files/78504213843.pdf
    • http://wmhsclassof1977.com/clients/34196/File/zatawadalomul.pdf
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606c93eda8715---1735795866.pdf
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/9oird27109e99r6hjc2s21kga2/39935946338.pdf
    • http://yogathoitrang.com/quangbasanpham/app/webroot/upload/image/files/rerade.pdf
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/6dc29d334dd3d1fe3af98b5b143dd43b/jumititupakemerodopumine.pdf
    • http://iphysiology.ru/upload/tebibadubivotasipavove.pdf
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c555d84c667---81044184160.pdf
    • https://propertiproperty.com/Uploads/userfiles/files/55277168742.pdf
    • http://softwarefactory.nl/images/file/jafumexajive.pdf
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1609b5d7eb8d3c---nodetokomujefixubekebepej.pdf
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609044c988ebf---saxonirubovina.pdf
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a458aa07201---zawiva.pdf
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/f7uc5tnvp8itiplq2o0a2bun2m/refurevamumafepapef.pdf
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160a0c6a28c5fa---22570761439.pdf
    • http://aclamerica.com/customers/CMS-IMAGES/file/lapirizazukimedi.pdf
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609913cde7229---65736187751.pdf
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/12bae2519271993eba388b73d79c72ad/3022887177.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=all+paws+rescue
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • 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_off0000be65.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBE65 16792 bytes
font_01_sfnt_off0000d67c.bin
eb860314356146c256615ba8f30a18f0f54f6d81c38b7342de023e4d4b5325f6
pdf-font-stream PDF embedded font (sfnt) at offset 0xD67C 10120 bytes
font_02_sfnt_off0000ed57.bin
4dcca63c5d0618034e5b9128852ea37b35e29854c4ad606713031a5d298dc19d
pdf-font-stream PDF embedded font (sfnt) at offset 0xED57 16776 bytes