Malicious PDF — malware analysis report

Static analysis result for SHA-256 5e15641dbc189900…

MALICIOUS

PDF

70.3 KB Created: 2021-09-25 03:43:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7c22241c20326f0212bba737d1ad73c7 SHA-1: 51b53fd7d50f4eff029cf4b1af3e40bc04444cff SHA-256: 5e15641dbc189900824dbdc3ec24c350848c7167c8a4cf88aa7e0277dc5681a0
96 Risk Score

Malware Insights

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

The PDF file contains numerous external links, with several heuristics indicating it functions as a link farm. Notably, some links point to compromised CMS upload storage, suggesting a potential distribution point for further malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://philabc.ru/uplcv?utm_term=why+does+app+keep+closing+android PDF link annotation
    • https://mobilieroccasion.fr/uploads/file/vibewatulazaja.pdfIn PDF document text
    • http://laros.cz/UserFiles/file/63361203977.pdfIn PDF document text
    • http://gzcil.com/uploadfile/files/mutefuxelizorexediboner.pdfIn PDF document text
    • http://myucmas.com/userfiles/file/90421497634.pdfIn PDF document text
    • https://ccichn.vn/data/upload/file/96534774103.pdfIn PDF document text
    • http://xtra360.net/campannas/file/butuluwijukozikuvudiba.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/sarej.pdfIn PDF document text
    • http://theclubburger.com/uploads/files/34193290501.pdfIn PDF document text
    • https://omnistopbollards.com/application/third_party/ckfinder/userfiles/files/lituvemuxebututizovuzimij.pdfIn PDF document text
    • http://h04ydivan.ru/userfiles/file/zujovufizuxuw.pdfIn PDF document text
    • http://4yoga.by/pics/files/94996603917.pdfIn PDF document text
    • http://csc0532.com/userfiles/file/20210914171506_v5pp17.pdfIn PDF document text
    • http://hanasushichoice.com/uploads/files/83288219872.pdfIn PDF document text
    • https://novsport.com/content/File/vaxafa.pdfIn PDF document text
    • http://boekenwinkelindex.nl/images/uploads/patodokewivukasuboj.pdfIn PDF document text
    • https://vallejardin.com/wp-content/plugins/super-forms/uploads/php/files/aa76cd7547f2f93f8c630d2fcebb3390/99916786982.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/d843a706d413dc270d1f44ffe58b349e/xatolid.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e0f7faa0a2---ridarojunu.pdfIn PDF document text
    • https://villadorottya.hu/uploads/frontend/files/15588301886.pdfIn PDF document text
    • http://ephtour.com/FileData/ckfinder/files/20210914_E7BABA9A42671853.pdfIn PDF document text
    • https://www.aukuras.org/ckfinder/userfiles/files/bapimoxidepakewekuzigipuz.pdfIn PDF document text
    • http://fittbikese.hu/files/file/xetoma.pdfIn PDF document text
    • http://jtylek.pl/Upload/file/10636634239.pdfIn PDF document text
    • http://parzenica-bialka.pl/userfiles/files/sewebojetiwigonaluxovele.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://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_off0000b37e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB37E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB90 15648 bytes
SHA-256: 71c049784512786c4e552267a6a480f57b815c04f9f9ed77ae54879ad35bbd37
font_02_sfnt_off0000f26f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF26F 10896 bytes
SHA-256: 94f2881fd717473f79f189f5aab06504714f1cc9903c509646487580a1d40ec8