Malicious PDF — malware analysis report

Static analysis result for SHA-256 5de28f3b50e331e7…

MALICIOUS

PDF

96.4 KB Created: 2021-06-29 13:50:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e3b4892da33a91e5fe598a4087e2409a SHA-1: 371f4cf8f2bcd3df088a08842e27556e4bc6cab7 SHA-256: 5de28f3b50e331e77a6fc115c094d41da4c3dbf16de925c41926fb894253c9bb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous external URIs and link farm patterns, suggesting it is designed to redirect users to compromised websites or phishing pages. The presence of embedded URLs and link farms points towards a phishing or malware distribution attack pattern, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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 https://synerhu.ru/uplcv?utm_term=dehiscence+meaning+in+english
    • http://mikailang.net/userfiles/file/20210505191943_1122252670.pdf
    • http://sarlampa.ru/upload_picture/tiranenubopebakavepe.pdf
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/122e17ae3073d9f2ab6b1368a35abbde/zalutotelibafen.pdf
    • http://kubabus.cz/novy-web/upload/file/23747211119.pdf
    • https://apz-arte.com/ckfinder/userfiles/files/kofuxolipugesapekibodose.pdf
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160c3a1f5790d9---wilifolitijoxuvoramu.pdf
    • http://noithatnhapkhaugiasi.com/luutru/files/junexis.pdf
    • https://network-italia.it/file/dugelofowuzitex.pdf
    • https://deepex.hu/hirek/files/35748219955.pdf
    • http://samtekelektrik.com/files/pabojan.pdf
    • http://kaupa.cz/userfiles/file/96420436189.pdf
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/f5fb9e9f928e05fd633605d6a92760ff/reviwiselanujupevavo.pdf
    • https://pellevah.com/upload/files/49497611018.pdf
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/160d36ebe14987---bupobuwedojiporefekamatu.pdf
    • http://anthonyvienna.com/sites/default/files/file/fubojodepevokurusaliwi.pdf
    • https://angelsstaff.com/uploads/file/vijina.pdf
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160779f6297ef3---27331977590.pdf
    • http://aprendanow.com/wp-content/plugins/super-forms/uploads/php/files/d6a7669adc00a37f0aa346c48df98d01/bemiwadekop.pdf
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/a833c1e3798a6f8cfa24cf4b46a4483b/93626155932.pdf
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160bd9aea8e9e9---27980616316.pdf
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16075a697b30fe---jomuvugopilipamivapudiw.pdf
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/466ofk1fnrcurpvu8urj988v1j/96870915173.pdf
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/c8057a36a2637b3769d1e9c8186dd666/gujizamofixajatefefo.pdf
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b57bd3c7f00---gusosafezalidefir.pdf
    • 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_off00011047.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11047 16792 bytes
font_01_sfnt_off0001285e.bin
02d6c8c819407d78f2454ccc6d38b51f73bf265e9f0c7fdeaec62c213411de9c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1285E 10360 bytes
font_02_sfnt_off00013f85.bin
2bd397c715c8778ce581f87a12118c6db41880cac09d5686f3da4c66aad093ee
pdf-font-stream PDF embedded font (sfnt) at offset 0x13F85 21568 bytes