Malicious PDF — malware analysis report

Static analysis result for SHA-256 0e60ff5407425821…

MALICIOUS

PDF

93.9 KB Created: 2021-08-25 15:16:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 7bcf6456f136ef8ed4d2d1c6ade1627e SHA-1: 4c0616513cb6ff785b681fc6f53c493ccdd7322c SHA-256: 0e60ff540742582182bbda380724d5b2722258f68396355f647b856985befe4e
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1190 Exploit Public-Facing Application

The PDF contains numerous external URIs and links to compromised WordPress upload storage, indicating it functions as a link farm. The ML classifier strongly flagged this PDF as malicious. The presence of multiple links on disposable hosting and the use of UTM parameters suggest an attempt to manipulate search engine results or direct users to potentially malicious sites.

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://krisoc.ru/uplcv?utm_term=thank+you+for+writing+a+letter+of+recommendation PDF link annotation
    • http://www.marcado.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16078e282a803d---weligifudemurizekilokum.pdfIn PDF document text
    • http://bagiez.com/userfiles/file/tisuleto.pdfIn PDF document text
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb46233303---xosazipezewefuvarita.pdfIn PDF document text
    • http://www.netcorp.hu/data/editorfile/66785319652.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/d68840020a96053ee426bc57cb46b23a/saruvelexi.pdfIn PDF document text
    • http://dongzzang.com/userfiles/file///rejolotebibigidizivuko.pdfIn PDF document text
    • http://jkbprivateiti.com/userfiles/file/dogiwolexuref.pdfIn PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160759304875d4---68572483531.pdfIn PDF document text
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/u862b145t7vkfm7blb2i9s1u69/76167067526.pdfIn PDF document text
    • http://parentini.it/userfiles/files/nutojomagabejuf.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/5e0ad5f10d59b3e97ef9b5451ed2ab06/xadakux.pdfIn PDF document text
    • http://jerilyndavisrobison.com/clients/870655/File/dewupeje.pdfIn PDF document text
    • http://3qbuy.com/CKEdit/upload/files/98006078770.pdfIn PDF document text
    • https://doitoutdoorz.com/file/IqyZOHsgxXCiCRpU.pdfIn PDF document text
    • http://k-sta.kr/FileData/ckfinder/files/20210715_B9CC9051FC33F7B4.pdfIn PDF document text
    • https://leavingcare3plus.ch/userfiles/files/fijekadetirodiva.pdfIn PDF document text
    • https://www.treehousecare.org/wp-content/plugins/formcraft/file-upload/server/content/files/16074d32d7ebcf---patuxitasokinupepi.pdfIn PDF document text
    • https://rosebankprimary.co.za/inc/ckfinder/userfiles/files/nodofuwogepikisexeka.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/160f0ed007d836---vimelitimobuda.pdfIn PDF document text
    • https://topclassgreenery.nl/images/file/bapesalamexubul.pdfIn PDF document text
    • http://pastoret.it/userfiles/files/velezalibakinurizufaziv.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a594f8edc5e---10568204256.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ace29c8b47d---zanimujopubuzafeb.pdfIn PDF document text
    • https://sambelteri.com/contents/files/witiselodub.pdfIn PDF document text
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/796c99616a74b6258df2a5571aecb5e9/62073067207.pdfIn PDF document text
    • https://performanceltg.com/wp-content/plugins/super-forms/uploads/php/files/1028414e7888aa97adc5ea8f79125d8b/lupezup.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_off00010971.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10971 11108 bytes
SHA-256: 2a9e92932aa08c137828e494a98e5a7b8599e66b9ba0530ac049637733e42adb
font_01_sfnt_off00012309.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12309 16788 bytes
SHA-256: 8da1c52bc9af945d7a5d4986ac18e99fade02fcbeb1d2cd398da4ff77a06be94
font_02_sfnt_off00014ec5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14EC5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1