Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b18b72e24076a4f…

MALICIOUS

PDF

82.3 KB Created: 2021-06-12 03:12:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: aa45bc8ad2b619e897f7c4dfef2c7f60 SHA-1: 41ec8e345242d5c6804fb8446621fc6b94562b4f SHA-256: 4b18b72e24076a4fe0d612dbbccdfb01cafe8cc0a14718befc3ab55ca691f8f8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. 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 0.9996

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://krisoc.ru/uplcv?utm_term=young+thug+pick+up+the+phone+mp3 PDF link annotation
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fd888ed1d3---65455068230.pdfIn PDF document text
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a2d2cabf120---siwutejedukobosimu.pdfIn PDF document text
    • https://nazragame.com/calisma2/files/uploads/53486554429.pdfIn PDF document text
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/099761a6495cb0243da4574d33e19bd8/99335888211.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083acb241811---69152148862.pdfIn PDF document text
    • http://centroolosprato.it/userfiles/files/68976914616.pdfIn PDF document text
    • http://irinaburmistrova.ru/files/luwizatewuxika.pdfIn PDF document text
    • https://webtraffic.ch/wp-content/plugins/super-forms/uploads/php/files/70mi6n4p9bsu8dl6nsdtl2sapa/96415784382.pdfIn PDF document text
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/3144c19366f334d8c04a6d4c307ce629/81717285844.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bf50ed3a94---vurozefitu.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080cd33e9d1a---pizage.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a26c1c2b8ad---91030272214.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/284c2375af6e3031898ec45e198ca9f6/wazapekefo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/7a744ede602b22b45e16f6f8a05f358e/48689318419.pdfIn 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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d864.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD864 4028 bytes
SHA-256: c13038d3a9907e0bc31cb0300bd3ef11349a9c139da4d057604e85a96e65bbcf
font_01_sfnt_off0000e68e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE68E 5020 bytes
SHA-256: d3ece6d0004cef0bb651c15629680a80d84723f0b5937ab5706bbbfe26f6d91f
font_02_sfnt_off0000f795.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF795 12216 bytes
SHA-256: 8639d91e193d9fd6810fa07c47d17ecfebc880defc779d49a31c2bd45f13b276
font_03_sfnt_off000120ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120ED 17112 bytes
SHA-256: 436829979245b7126098886beec731c3e32f79caaa22165f5cf5bd484c81a714