Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b8e4194c5011e45…

MALICIOUS

PDF

92.9 KB Created: 2021-07-18 17:17:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 96701649453cda73928261d3ae34e968 SHA-1: 40fdc5ae14908a5c162b5d5a3babd21138fe93ae SHA-256: 4b8e4194c5011e45d709b6e6459121d74eca642067b0088f1f18e08dfd46858c
96 Risk Score

Malware Insights

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

The PDF file was flagged by an ML classifier as malicious and contains numerous links pointing to compromised CMS upload directories and disposable hosting. The document body is heavily obfuscated, but the presence of a link farm suggests an attempt to direct users to malicious websites, potentially for phishing or malware distribution. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • 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://zonwering-nederland.nl/ckfinder/userfiles/files/60277256626.pdf In PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c2965c32a08---sebuzoxatapigezale.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2f3dfe333a---12674749948.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160811273559ab---73914890009.pdfIn PDF document text
    • https://cncostruzioni.com/userfiles/file/57435229806.pdfIn PDF document text
    • http://auroraenergyproject.it/userfiles/files/kesavobumoraxotebofek.pdfIn PDF document text
    • http://farmaciafasolis.eu/userfiles/files/15583248151.pdfIn PDF document text
    • http://cgpreceptor.com/ckfinder/userfiles/files/7782143210.pdfIn PDF document text
    • https://rabudiagnostic.com/userfiles/files/tiredisofud.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a18788c711f---44669344054.pdfIn PDF document text
    • https://mygoaltv.org/ipp/images/uploads/files/19470394022.pdfIn PDF document text
    • http://dodici12.ru/wp-content/plugins/super-forms/uploads/php/files/l1d7pj9vptp2rjiqra7sd00nk7/36213156589.pdfIn PDF document text
    • http://tplustech.com/images/ckeditor/files/vidovujojetizaminabakolef.pdfIn PDF document text
    • http://airholic.com/UpFiles/WebEditorFiles/file/54388638940.pdfIn PDF document text
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609a866ce188a---31814323771.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/ss60ook9p39649gqhin3jbtbb0/85653090400.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160910d8eeaf1b---86804772711.pdfIn PDF document text
    • http://maketmaster.ru/admin/ckfinder/userfiles/files/gamom.pdfIn PDF document text
    • http://poiskvod.ru/images/file/bowirosesiwisetuva.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/h63ml5qmbf7gh9vh3c3ai0khp2/61451508868.pdfIn PDF document text
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/1476f09402c4b127144634feb6c4ef73/36598150925.pdfIn PDF document text
    • http://mousike.it/img_ins/files/vujisufujetofifuwa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=girl+from+nowhere+episode+1PDF 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_off000107cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107CB 10680 bytes
SHA-256: 6c6fab2f5823537e63fbb247ad5104d59fae06c8c90481a8e836d83941ea3dc6
font_01_sfnt_off00012017.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12017 17684 bytes
SHA-256: a834a4499fa2e6a480710207f5c3219d92a2b0b019fd2961aca4cc710c00b58f
font_02_sfnt_off00014eb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14EB4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1