Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5525ae316ab059a…

MALICIOUS

PDF

89.5 KB Created: 2021-06-26 08:10:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b24686139a6a89790f16c8e63d4dee83 SHA-1: 00deb3e01237b80030413e90f7222c03f639a76d SHA-256: d5525ae316ab059a9b0ec6382da5194ff4f21ac17a13aa329868129e4e57b2b7
96 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to compromised CMS upload directories, indicating a likely attempt to redirect users to malicious sites. The ML classifier strongly flagged this PDF as malicious, supporting its use in a phishing or malware distribution campaign. No scripts were extracted, but the structure and URL patterns suggest a downloader or redirector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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=the+great+gatsby+chapter+6+vocabulary
    • https://medgarlci.com/wp-content/plugins/super-forms/uploads/php/files/8371ff744e0bdc6d1aab1e3fa2b36325/7085362489.pdf
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/79b98af53accfde57176ae41042f6c93/5516655425.pdf
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/bd99e6c652b51456726c8a7ff7b3edb1/xavisinorinoxuf.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/ivl3sfb5cag32o70juhveq3u44/berufi.pdf
    • http://edu-family72.ru/content/images/uploads/file/zevugobojaxalilijirobukag.pdf
    • https://cakenepal.com/userfiles/file/38277233421.pdf
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/3ea0515225efb1fd103c815c560bdbbc/wedosafigidosifowiwezovi.pdf
    • http://creativeindustries.ru/uploads/userfiles/file/jagajovupadikamoselak.pdf
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/160b50222632d1---34762477286.pdf
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b09b9e1a35---60720921588.pdf
    • http://bygreenpure.com/userfiles/file/72549336877.pdf
    • http://uss100.com/clients/5/56/562308f4da1da23328cfd9e5c9f3e68f/File/80467368288.pdf
    • http://nacyc.jp/Upload/file/77868619412.pdf
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a89f976127---ruzode.pdf
    • https://p87.hu/files/boxalonusetexepujor.pdf
    • http://www.alfapilates.pl/upload/file/63469600508.pdf
    • http://jfhcoaching.nl/userfiles/files/wedake.pdf
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/86e162fb26f226e93be0b4195f07ffee/filareto.pdf
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/196413c12ad1250438e6e9683cdf4866/76534821504.pdf
    • http://seanmore.com/userData/board/file/75025143365.pdf
    • https://carstenrath.com/wp-content/plugins/super-forms/uploads/php/files/6rvhoh6cfbo8hbut1v1upc5lop/kanosituw.pdf
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/ca7f8b0e5d37212efe2bcad614d1cb08/28095338423.pdf
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/c74090e1bb6053477c80a110f0bbdc51/mevurenivomemaveribex.pdf
    • http://imagespa.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160a3380f61f21---zipufozafadasabon.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/160b9a867c6fb8---kojixafarara.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f9bb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9BB 16792 bytes
font_01_sfnt_off000111cd.bin
ab3476bc560f88d738b1c76b63d601b9e015024b38dc66e7190ff226cde1409a
pdf-font-stream PDF embedded font (sfnt) at offset 0x111CD 16824 bytes
font_02_sfnt_off00013d3f.bin
497029596bd5e07adb503fa344859ee0c034279ee3693e29004126007b2cc1ee
pdf-font-stream PDF embedded font (sfnt) at offset 0x13D3F 11008 bytes