Malicious PDF — malware analysis report

Static analysis result for SHA-256 99c0a2cb55621bf9…

MALICIOUS

PDF

82.0 KB Created: 2021-06-17 14:38:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 9962926ddb68573edac321b1afd23db0 SHA-1: 81c4fb7a8fc8bf69bfc40786311d13145bab41e3 SHA-256: 99c0a2cb55621bf9e71d34ba7a29058004433f88999339cdc92cdf0a963b5db1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://coretry.ru/uplcv?utm_term=unicorn+cartoon+coloring PDF link annotation
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160718b40cf4d3---jasudazaxadupuvunizin.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609e86f6a3d70---jalumufiwenujamubadolema.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/teluzenebadusofopol.pdfIn PDF document text
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/2d4ob4pmpqvfk7abi8r4f69nab/97189094406.pdfIn PDF document text
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/3303377a61ccf05c14bf489bef7070b3/gomujeveburodexigop.pdfIn PDF document text
    • http://menafundinfo.com/userfiles/file/89804095409.pdfIn PDF document text
    • https://sancarspune.com/wp-content/plugins/super-forms/uploads/php/files/bc478410c88e84697d962ae9b64f6933/xulelarebojefofiderisomo.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce11118812---gulodifa.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077b8d254f2c---vifogifowatevupega.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608447da4d7ea---37504949970.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/1223a283038dbda9dafa8d7d1631d5bd/kujovolozeravusupurifuter.pdfIn PDF document text
    • http://applexin.com/ttpsea/files/file/nafeguvunejumujugup.pdfIn PDF document text
    • https://www.jscorporation.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1609c31c636ad3---85070704421.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093fa39b38f4---wukafi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f944.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF944 4452 bytes
SHA-256: 781116fc822752de9bb3be095e43bce6d3194878128f275e694e60f51f45c059
font_01_sfnt_off00010853.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10853 10856 bytes
SHA-256: b9c1f8dfc5d09a7a8d76a518768a39fd483941495485bebf56271653584deead
font_02_sfnt_off00012cf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CF2 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34