Malicious PDF — malware analysis report

Static analysis result for SHA-256 843451b10cadd144…

MALICIOUS

PDF

77.7 KB Created: 2021-09-04 03:21:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 575fddbabe0d761cd1141572d43c4922 SHA-1: 4bee83176db0af5130c11b30ed6528e9e37eb415 SHA-256: 843451b10cadd1447b17d4c3fbd87caac8ac25543bbff5328cc43bb8b8f2cede
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these links and the overall structure point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://infrive.ru/uplcv?utm_term=perfect+day+piano+sheet+pdf PDF link annotation
    • http://yevres.fr/ckfinder/userfiles/files/pedinebasodibazule.pdfIn PDF document text
    • http://effektfilm.de/files/file/80247318890.pdfIn PDF document text
    • https://crbz.ru/userfiles/file/xelevoxukuwasife.pdfIn PDF document text
    • https://coffeetuanvang.com/Images_upload/files/13316386633.pdfIn PDF document text
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/2c6e85adb6cd9e39e73417249afc7c0d/salusewawirekawamaze.pdfIn PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/9v8duv789s467f4qbamdakra75/juxumaroburo.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/160aa0edd4bffa---zogijav.pdfIn PDF document text
    • http://ajisushionline.com/uploads/files/31995155433.pdfIn PDF document text
    • https://forthepeoplegov.com/userfiles/file/pabagubunegabifegoli.pdfIn PDF document text
    • http://joyerialaplaza.com/ckfinder/userfiles/files/xafazenuzojikizewerama.pdfIn PDF document text
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160849ccf8f2ad---3314225869.pdfIn PDF document text
    • http://china-baby-clothes.com/d/files/32135880944.pdfIn PDF document text
    • http://seoulmenu.com/uploads/files/nedakixoj.pdfIn PDF document text
    • http://agama-rc.com/upload/files/gaxifimezo.pdfIn PDF document text
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/160903707a835d---pebolosi.pdfIn PDF document text
    • http://eska-lift.ru/userfiles/file/gagugen.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/51c2d46c92ac00129ce8a575aa5d2a24/baladufamiz.pdfIn PDF document text
    • http://konferencii.org/web/uploads/assets/file/83175396985.pdfIn PDF document text
    • http://ladakhtripmaker.com/userfiles/files/81557004547.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/b97fc996a722f4933e62b3509cfa8a86/59171001216.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_off0000c744.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC744 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000df56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF56 18652 bytes
SHA-256: 6b7197ddd9ee638044195c202b836ab36a2be322b2f9d01f4228872778ea40a0
font_02_sfnt_off000110fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110FA 10784 bytes
SHA-256: ad84e1625e7b2f5648d00dea019a6b9f8bce9dc1ac7f33c10642a10cd6d723cb