Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1ec125ddf937c1b…

MALICIOUS

PDF

103.0 KB Created: 2021-09-21 09:55:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: ac61bb4ef31308287405a2b0002098f0 SHA-1: c9b49d46214a8321486ecfe9826921e039733483 SHA-256: c1ec125ddf937c1bdca351fdc49ee02b3449747296984d0c23c4dc2f95602b4b
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous other PDF files, many hosted on domains associated with compromised CMS uploads or disposable hosting. The ML classifier strongly indicated maliciousness, and the structure suggests an attempt to manipulate search engine results or distribute further malicious content. No scripts were extracted, limiting the analysis of direct execution vectors.

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 http://epoxidice.ro/mm/file/jewerirezonugat.pdf In PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/161456f7dee303---5747490256.pdfIn PDF document text
    • http://suliaok.com/v15/Upload/file/2021919227404756.pdfIn PDF document text
    • http://getvisa.ru/images/File/jukitubatilakovid.pdfIn PDF document text
    • http://iccjsc.vn/images/uploads/files/52908195654.pdfIn PDF document text
    • https://a-pointpro.com/cms/ckfinder/userfiles/files/tutuselurofimenuvebej.pdfIn PDF document text
    • http://kutyasturak.hu/images/files/61410978963.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/vawivazaxab.pdfIn PDF document text
    • http://magic-mugs-factory.com/uploadfile/files/60991197083.pdfIn PDF document text
    • http://www.everhouse.lt/wp-content/plugins/formcraft/file-upload/server/content/files/161406a513a62d---80649352235.pdfIn PDF document text
    • http://a1-automotivegroup.com/upload/files/lawuvuserixotolifuduvuzin.pdfIn PDF document text
    • http://ttccid.com/userfiles/file/muwonapi.pdfIn PDF document text
    • http://gloria-eurex.com/images/blog/file/60971699785.pdfIn PDF document text
    • https://dukeofmarshall.com/ckfinder/userfiles/files/ripikerulupegobixuvuj.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613d35211dca4---lovobubejelesanixideziwuf.pdfIn PDF document text
    • http://zpb-maciejewski.pl/upload/fck/file/bubeforufujotaguxewukinik.pdfIn PDF document text
    • http://symbolfoods.com/files/file///senopiwarixeruwu.pdfIn PDF document text
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148fda913f39---lejuromijana.pdfIn PDF document text
    • http://tcsm62.org/uploads/news/file/tisegapaparozarodupef.pdfIn PDF document text
    • http://shepardinteriordesign.com/rw/upload/file/83352267709.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141c311a41c6---9669553856.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=square+root+of+10+squaredPDF link annotation
    • http://s292376414.onlinehome.fr/datas/imgmail/file/20230843165.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_off000129f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129F7 20076 bytes
SHA-256: a398ebab5646d0ef7017b4590e508ee46dc6815dc530bf47d0927acc86f19dc5
font_01_sfnt_off00015e2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15E2A 10600 bytes
SHA-256: 3a07215635ebf59eaeb9255d3dd658a441e60ed46f3233e2ba664d0cd3886eac
font_02_sfnt_off0001765e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1765E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1