Malicious PDF — malware analysis report

Static analysis result for SHA-256 86d16cbae5151e81…

MALICIOUS

PDF

79.2 KB Created: 2021-08-19 12:27:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: c0d83a4fa56de2594cb588fc979401b4 SHA-1: 339023a25356db85fa3df5192467fd83f9051230 SHA-256: 86d16cbae5151e81b26e290404f528706ba9d7ac968a8bb575365a7e3c89f3fe
96 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites and disposable domains, indicating a link farm designed to manipulate search engine results or distribute malicious content. The ML classifier strongly flagged this PDF as malicious. No scripts were extracted, but the heuristic firings suggest the primary function is to redirect users to external, potentially harmful, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://midel.me/userfiles/file/67313521903.pdf In PDF document text
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/dcceebf7cdd57580d9221f68c83fc95c/76083744912.pdfIn PDF document text
    • https://sce.tw/uploads/files/60ff5e5d74f31.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/woxetowajisurabirujiti.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072cdc89083f---zilevanevalekoripipadumu.pdfIn PDF document text
    • https://isleo.com/i_photos/file/sisobalala.pdfIn PDF document text
    • http://brkvinc.com/userfiles/file/43428915037.pdfIn PDF document text
    • https://greenturtleproductions.com.au/wp-content/plugins/super-forms/uploads/php/files/9d4d9926f4a60fe809697886967c9296/pelodexebuf.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/b9ed79ed0b9cccf5ad2f7eabd97ff87c/vanuviwinatoregoluwe.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a71344e8450---18892654292.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/o7hsui6evaahdav8uvta0u8cjq/13580215902.pdfIn PDF document text
    • https://abofahed.com/userfiles/file/84012743922.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/ebf9674147adc162ca3bfd477d05788c/kakativ.pdfIn PDF document text
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/77e20469c7cdb450328c301f8a6172a5/42902837536.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160801383c6cfa---84137598610.pdfIn PDF document text
    • https://martensmgt.com/business_school/uploads/file/80859207160.pdfIn PDF document text
    • http://alfavit.tv/userfiles/file/kovowa.pdfIn PDF document text
    • https://dienlanhhonganh.com/images/pic/file/45341505129.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/4b40e24b03663d8fdac6f91206b23bd5/zopanuduxak.pdfIn PDF document text
    • http://www.chatanakonci.cz/userfiles/file/93803846804.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/om4sr9a50338123sf325jqf1jk/bemepuzalobarurebukosufiv.pdfIn PDF document text
    • https://razvozka24.ru/wp-content/plugins/super-forms/uploads/php/files/3c174d9e743b98de9648299918d3a931/repanepitaluvife.pdfIn PDF document text
    • https://inijariku.com/ckfinder/userfiles/files/wuwimofevezanu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=the+legend+of+zelda+ocarina+of+time+3d+guidePDF 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_off0000d168.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD168 16948 bytes
SHA-256: d7611112468229570bb7e4e901ff120e794aa18b9bdd109c3f2789f0b9ba68f8
font_01_sfnt_off0000fdd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDD5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000115ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115EC 11052 bytes
SHA-256: 0d0c80de1541b42bc88835bfa29b93eef3cc01e3106f2751786f92431b94b6c2