Malicious PDF — malware analysis report

Static analysis result for SHA-256 cc764bfc8beb859f…

MALICIOUS

PDF

82.6 KB Created: 2021-06-27 04:28:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 26170ae517bd829c9f9e94cdd8f0bcd4 SHA-1: 123a30aa73ebfe86296612eafebb983fb34e084e SHA-256: cc764bfc8beb859fa0fa4679ecb64e4f5e4b871560b8e5ce9527b29294d9afa8
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to numerous compromised WordPress upload directories, suggesting it is used to distribute malicious content or phishing pages. The ML classifier and ClamAV detection strongly indicate malicious intent. The file's structure and numerous external links are consistent with a phishing or malware distribution lure, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://juniorsmagazine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073e94383fbb---80279466272.pdf
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/160cad51c2f017---15180050739.pdf
    • http://ldbell1965.net/clients/85689/File/36044522294.pdf
    • https://actor-conseil.com/files/file/5448989219.pdf
    • http://neuragen.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16094781047a71---39054203140.pdf
    • http://hyunbulsa.org/~ewedd2/userfiles/file/kutokuwatojufigogagopipen.pdf
    • https://nepalipublisher.com/ckfinder/userfiles/files/nutiw.pdf
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608193c2e969c---neputonabesavewopu.pdf
    • http://agcslohian.com/userfiles/file/91061875833.pdf
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/2b281db86d96954c1b213d85f74daaa4/tiduviju.pdf
    • https://baohohoanglong.com/userfiles/file/16857263391.pdf
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2791153c4f---87554272268.pdf
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606d41121d946---81242217535.pdf
    • http://anhuifan.com/upload_fck/file/2021-5-8/20210508191125153797.pdf
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/67d030ada8c70afeaa6531dfeff9d8c6/85210333182.pdf
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/eka1ie31ke9h2thcs1usmqa487/6561093113.pdf
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/96g8g9jc17hbnb7tv3aej0lgdu/wumufa.pdf
    • https://athensviptour.com/wp-content/plugins/super-forms/uploads/php/files/4756b4d4160db7aaef1f91b291286cb3/tosenuwagebanifudevitopen.pdf
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bd9c06c7102---34125076087.pdf
    • http://gongotour.com/FileData/ckfinder/files/20210626_6B9858FBEC5A1912.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=13+gb+to+mb
    • 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_off0000df8a.bin
1718617c1c0fd64592ccd1a8e0a3aabab1d2f97467776f455c8e7d0c7ae3828b
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF8A 18004 bytes
font_01_sfnt_off00010e79.bin
c9608447879244a4614dbbf892d040fcc57e37f1357cbd9b0021ad3ebe514b46
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E79 9912 bytes
font_02_sfnt_off0001245e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1245E 16792 bytes