Malicious PDF — malware analysis report

Static analysis result for SHA-256 53b4e395ef450c74…

MALICIOUS

PDF

81.3 KB Created: 2021-06-13 07:51:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: ae07ea62ec4cc6aac28b4777b07f3b6e SHA-1: 0815d92742804640f8d5bf5a133d400887d02c25 SHA-256: 53b4e395ef450c74d12a08581f8034c9b8f05a3985b04a8f4599c72a6230d347
196 Risk Score

Malware Insights

MITRE ATT&CK
T1059 Command and Scripting Interpreter T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a clipboard-command (paste-and-run) lure. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clipboard command execution lure high SE_CLIPBOARD_COMMAND_LURE
    Document tells the user to copy or paste clipboard content into Run, PowerShell, cmd, or another shell-like execution context
  • 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://chcial.ru/uplcv?utm_term=can+you+copy+paste+from+a+pdf PDF link annotation
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a097b878c64---57228026337.pdfIn PDF document text
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bca612c550---1521330187.pdfIn PDF document text
    • http://baschin-heizung.com/meineBilderAlbertGrundschule/file/gonivijuwaxexaw.pdfIn PDF document text
    • https://soba05.org/wp-content/plugins/super-forms/uploads/php/files/901d125aed5ffa3b6ddd9f17543e0585/34840137971.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac592a02edf---danukebojedowekadudam.pdfIn PDF document text
    • http://sacoorhealth.pt/site/upload/file/91969226366.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc69db77f8---tejomegejuzawak.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/mnsesr5l1je258pdbeu2dil45m/mobumugofunuxitab.pdfIn PDF document text
    • http://goodwill.as/userfiles/file/18970167473.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160bb40e7b3beb---gigolulelovojutoxeri.pdfIn PDF document text
    • http://anhuizpyy.com/upload_fck/file/2021-5-2/20210502224525181507.pdfIn PDF document text
    • http://www.goldenlantern.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16071ed800a8d4---51123612167.pdfIn PDF document text
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/b1f915f7918d4d2380818b0eb4c30419/51998511784.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160aa5c3cb555c---nifurutorapisedisuf.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//25696094302.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607803fbd1fd1---mogevo.pdfIn PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608408c5cf590---6964948005.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e9ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9FF 5228 bytes
SHA-256: 41ceb067448e822a780541a9072c178bc8e7b5b2a915153d901cc6882f16123a
font_01_sfnt_off0000fbb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBB6 14868 bytes
SHA-256: 1501fd39f5b0d82f221a0a53441563c5c9e563173765b5bb2613cef903a85591
font_02_sfnt_off00012a38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A38 4324 bytes
SHA-256: 7f6049e5011acf0e8581793f2bc2bb947aac2929fdb77abc318b2a6155c1ef71