Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf6fd34f0937e581…

MALICIOUS

PDF

78.7 KB Created: 2021-09-01 02:31:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 0c279daf8d16781c9f8c04aa4aae9f20 SHA-1: 90c15ae2fec8a5efb135c7403e0868e8c881592f SHA-256: cf6fd34f0937e581758edaacb73b040772d9fbe9f526ab9bf57e3b433cb9e6af
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress sites, indicating a phishing or malware distribution attempt. ClamAV detected this as Pdf.Phishing.Trojan, and an ML classifier also flagged it as malicious. The presence of multiple external URIs and a link farm structure strongly suggests the intent to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://bobiniauto.com/userfiles/file/tesodunem.pdf In PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c0332716d7---desawi.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/d4a96160a375267170d67544f5e85556/kumovapunasugigexez.pdfIn PDF document text
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/143a0306935f6475787f5e16b60d2c88/vogimurelivisilovoje.pdfIn PDF document text
    • http://signexpowholesale.com/project-new/christianbook/upload_images/file/85364757640.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a38c49539eb---mawoviweniwoxomala.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/7d9da22467e6ab9dea4d38291f0a4687/96673680567.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b8aac28405a---konaxowizefesatajasatufu.pdfIn PDF document text
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/633580012e15ecca375da82ee552540e/lonebugosepudipojoxenav.pdfIn PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b79f2b30e3---24880220143.pdfIn PDF document text
    • http://rockefellersgold.hu/editor_up/57284766237.pdfIn PDF document text
    • http://matchedtubes.de/userfiles/file/zepukemowite.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/32sth2vd9k5koiko3duguj4c04/tininipepuno.pdfIn PDF document text
    • https://ontech.vn/images/ckeditor/files/47872972570.pdfIn PDF document text
    • http://leasingtowers.com/ckfinder/userfiles/files/fofifino.pdfIn PDF document text
    • http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609016b4e9eac---37845359195.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bafae8a9aa---50988184282.pdfIn PDF document text
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/0b29b2bb3d8a0c40373886d2cafb6083/werifepiwefezit.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/5emb03mmjooeaqmm0e8b7m5auk/lifiwajutesivozebige.pdfIn PDF document text
    • http://newgatedesign.com/Images_upload/files/kirejof.pdfIn PDF document text
    • https://t2sc.me/userfiles/91397008520.pdfIn PDF document text
    • http://youngshiny.com/userfiles/file/1621444160.pdfIn PDF document text
    • http://csc0311.com/userfiles/file/20210621062621_j4uuzr.pdfIn PDF document text
    • http://thicongdiennuocmiennam.com/uploads/files/dulegozobug.pdfIn PDF document text
    • http://ipceurope.eu/assets/file/wogulezogetakafu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=the+five+minute+journal+pdf+downloadPDF 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_off0000cd60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD60 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e577.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE577 10940 bytes
SHA-256: cec94a7b555ae4f1dd321c04eadeea5e560ad5cd8d7c148c195b7584b585dd54
font_02_sfnt_off0000fe96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE96 17972 bytes
SHA-256: cd213564345103ff3190021af39f31dd7173bd4a8b528a7f8e4f9aa2b9a56aa9