Malicious PDF — malware analysis report

Static analysis result for SHA-256 b98f4ed4279a3a8e…

MALICIOUS

PDF

83.3 KB Created: 2021-07-09 09:28:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 473259973d22dde6713c745c23876703 SHA-1: 767fa1669848baf0c4bc2f43a397e19ce82e09d4 SHA-256: b98f4ed4279a3a8e831d74f2909e1b7642d2f3e3f690a3b05f502e454963b94a
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories. The ML classifier strongly indicated maliciousness, and the presence of link farm heuristics suggests an attempt to direct users to potentially harmful sites. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://prosegik.com/wp-content/plugins/super-forms/uploads/php/files/233d9ba1261ec90fd789f8e2ca205914/13519071220.pdf In PDF document text
    • https://grandplaza.bg/uploads/assets/file/gasekuwitepofepik.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b16cc586a9---36066467655.pdfIn PDF document text
    • http://firmykominkowe.pl/Obrazki/edytor/file/83356312144.pdfIn PDF document text
    • http://www.anjhimayath.com/upload/file/sutedin.pdfIn PDF document text
    • https://qualitylightsolutions.com/wp-content/plugins/super-forms/uploads/php/files/4d30c2e1f11d76d6e5da9555c0d79830/zuzujafaxijoletolo.pdfIn PDF document text
    • https://travelsafeway.com/userfiles/file/wetemobogexazivana.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/rdkpd4hh7elvmom3rootum6dm2/39292283553.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/vpuk4lovvhg28b5ifc2d8ftedh/96865617752.pdfIn PDF document text
    • https://vientangluc.com/upload/files/29319517382.pdfIn PDF document text
    • https://whatproperty.ng/ckfinder/userfiles/files/96574687618.pdfIn PDF document text
    • https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/c8d2d011fadf560dd551608398b55bfe/tofotuxasinijemurapirenod.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/makibirosalefekariboza.pdfIn PDF document text
    • http://dzbnf.com/upload/file///dutowopisigu.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/e936f608115d12858542bdc886f985d8/151301156.pdfIn PDF document text
    • https://interesttour.com/wp-content/plugins/super-forms/uploads/php/files/4812d250f482b9276b408843c82d5402/21019996495.pdfIn PDF document text
    • https://esz.jp/img/editor/files/zikavoderi.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/a4oksph5jng1lhjnsr7bvk5ol9/1294103266.pdfIn PDF document text
    • http://sarlampa.ru/upload_picture/61824404745.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/521cf9d8521b1152a3afc8deb4d674cd/68168480720.pdfIn PDF document text
    • https://ildiko-szepsegszalon.hu/userfiles/file/tapenebezara.pdfIn PDF document text
    • http://anthonyvienna.com/sites/default/files/file/refemakezenagoporudod.pdfIn PDF document text
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/o6fltjv6nuie8b872gnl4nevm7/fedobemazava.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/b17c9955f842e228da52b809292b0d4f/jolufagejok.pdfIn PDF document text
    • http://be1971.com/clients/a/a1/a19be2fc4cf8b198b52f296748481ce5/File/duten.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=a+tiger+in+zoo+class+10PDF 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_off0000e2da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2DA 17048 bytes
SHA-256: 2981d822da69907a9b3d52c6a80778defa8cdde856cc94b73508c2afa9c81c35
font_01_sfnt_off00010f3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F3E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012755.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12755 10620 bytes
SHA-256: b8b34a9d06ab0f79095ec48c0ba843bf9eac7b71ab0df79cde1c5bf2dd0ee0a3