Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b495fff63fa13cb…

MALICIOUS

PDF

69.2 KB Created: 2021-10-01 09:52:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 6e624372c1045a7bb158a29542e14c18 SHA-1: 09afb998da97274088813e03305f2587c63e87aa SHA-256: 8b495fff63fa13cbbe569858e9a6a5a3b91628aaf74d2fc9ba6ed0554f7ae7fc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://inwebjor.ru/uplcv?utm_term=phone+recording+phone+recording PDF link annotation
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/e48e7a6fbed3777baf0308b736741bcf/wavadetekiwal.pdfIn PDF document text
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/069938437f89bdcb1b15700ecae22b4b/88356623274.pdfIn PDF document text
    • https://www.smartfutureexpo.com/ckfinder/userfiles/files/18378611183.pdfIn PDF document text
    • http://marjoleintje.nl/include/userfiles/29326693221.pdfIn PDF document text
    • http://arisutour.com/ckupload/files/47100373887.pdfIn PDF document text
    • http://silesiacapital.eu/data/file/sixitala.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/06d8198b8432146aba8d0a4ad47c20c0/gobigogigiva.pdfIn PDF document text
    • https://loyallcanada.net/editor_files/file/81809893909.pdfIn PDF document text
    • http://cu-hinothai.com/ckfinder/userfiles/files/42942013815.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613530e875c44---sotetifosek.pdfIn PDF document text
    • https://stgeorgedentalcare.in/ckfinder/userfiles/files/28184668428.pdfIn PDF document text
    • https://acrgruppe.de/userfiles/file/vumowuwurizoxutanotekil.pdfIn PDF document text
    • http://clubselectionvoyages.net/images/file/vokuloridufunoximu.pdfIn PDF document text
    • https://pierrelemagicien.com/userfiles/file/86298135796.pdfIn PDF document text
    • http://labotinnghia.com/img/files/78998975012.pdfIn PDF document text
    • http://imreelectric.sk/uploads/file/nedelamozubavetume.pdfIn PDF document text
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/jku7ekkvgqseihpnbekp1a7n9p/87228690396.pdfIn PDF document text
    • https://braindevelopmentmaps.org/userfiles/files/vekopalaxe.pdfIn PDF document text
    • http://locnuocvietmy.com/Images_upload/files/41776916725.pdfIn PDF document text
    • https://xtremefitness.com.au/application/third_party/ckfinder/userfiles/files/64088014014.pdfIn PDF document text
    • http://szermgrt.hu/uploads/ckfinder/userfiles/files/62261943137.pdfIn PDF document text
    • http://styropapex.pl/userfiles/file/69171591372.pdfIn PDF document text
    • https://tennis-samara.ru/img/file/26739426180.pdfIn PDF document text
    • https://web-dev.ethioapp.com/websites/lightyearsahead/code/userfiles/files/tigirizozofodiboj.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_off0000b20b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB20B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA1D 15076 bytes
SHA-256: 9027b878eabac258e85659e199b67b9bc56ae5b4ecba0622e486ca624799a797
font_02_sfnt_off0000f02f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF02F 10320 bytes
SHA-256: dc48e4a2487ce9e6c40da288841c0c90d230eeae33b39d3a1b678719eae925ba