Malicious PDF — malware analysis report

Static analysis result for SHA-256 5ea23455616dbbf8…

MALICIOUS

PDF

72.1 KB Created: 2021-07-18 07:42:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 8bdc5fc0622d8c3ca2a27bc0138d63b7 SHA-1: a0d06ac8aea3fc4079d5d23b5b425cb4cc7332fc SHA-256: 5ea23455616dbbf857774a3d97ae8051060d3c29f62beb085fd4b47d8245ceec
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, containing numerous URLs pointing to compromised CMS uploads and disposable hosting, likely to distribute further malicious content or phish for information. The document body was unreadable, but the heuristics strongly indicate a malicious intent through the extensive use of external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/2hvdem1njpqrg049nd805i1196/dasoxisotefutaf.pdf In PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160c645d5bf8a7---zamufubanet.pdfIn PDF document text
    • http://webursitet.org/Files/file/67153069162.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5c93647473---gibuwesevugigoso.pdfIn PDF document text
    • https://aonetreks.com/uploads/file/zedifodafibogo.pdfIn PDF document text
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/c2mc38725qkql1polr5o61u9e1/xobofakopu.pdfIn PDF document text
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1608562a55ff85---gobinoripojuva.pdfIn PDF document text
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/00cb95b7860fbca3f6f6652a0e17673d/dizebusog.pdfIn PDF document text
    • https://koratspring.com/upload/file/4313602111.pdfIn PDF document text
    • https://fishboat.hr/files/43727852750.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/d138i6o83g9go1n31vnvk6gemq/libimebogefumo.pdfIn PDF document text
    • http://castrolmintabolt.hu/images/upload/file/84913975192.pdfIn PDF document text
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/5ab16f8k2etde1gbhgl457h02g/kunanowuga.pdfIn PDF document text
    • http://debden.org/userfiles/file/genagodejitoxi.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a81afab3c83---51385744701.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/fd9cf5db62f1fd780d4feee7f6f11a97/1530010664.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/bb0d092f01d72b32e8843e3578ce72e8/jemagoge.pdfIn PDF document text
    • http://ventilyatsia-v-sochi.ru/ckfinder/userfiles/files/60972980724.pdfIn PDF document text
    • http://sochistandart.com/ckfinder/userfiles/files/nutixivorazusuze.pdfIn PDF document text
    • https://morethancleaningservices.com/wp-content/plugins/super-forms/uploads/php/files/c63eca2c88eb9a49757105622ea240b4/3843127316.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a9a78baf18a---jorubegidurew.pdfIn PDF document text
    • https://filetorme.com/upload/files/nadoxutijuzasamujusuluri.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160b5bcdbc1275---voxopumavebapidibivaxof.pdfIn PDF document text
    • https://wccia-vastu.com/wp-content/plugins/super-forms/uploads/php/files/5976b2ecfdde01b2972ccd674877300d/81977838887.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073f5a1b0532---50166624384.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=intortion+of+eyePDF link annotation
    • http://s292376414.onlinehome.fr/datas/imgmail/file/69972147405.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_off0000ba63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA63 9896 bytes
SHA-256: 8beee128bba7c4be7c642971b447d9796331932f9b698a5e889de821a9d638e5
font_01_sfnt_off0000d058.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD058 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e86a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE86A 16296 bytes
SHA-256: d1f56ee75a3d6e71be4fb21756bfbb555b2964573f968276b4c85d31fc4befcb