Malicious PDF — malware analysis report

Static analysis result for SHA-256 19ad56277fc7c338…

MALICIOUS

PDF

75.0 KB Created: 2021-09-12 15:17:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7a5ad8fdfd45406dba96b30aa22d7823 SHA-1: f746fc0414da636a3511367aa3a43445f1aeaf3c SHA-256: 19ad56277fc7c3381a0cb6053df4a4e9570603ad30944fcb24954538b62ba2f1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this, indicating the PDF's primary function is to act as a lure to external, potentially malicious, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://nomylo.ru/uplcv?utm_term=justice+league+unlimited+free+streaming PDF link annotation
    • https://khmernative-rice.com/userfiles/file/61417312612.pdfIn PDF document text
    • https://kham.vn/userfiles/file/73305016189.pdfIn PDF document text
    • http://duocthientam.com/uploads/ckfinder/files/domedumo.pdfIn PDF document text
    • https://calendarsunrooms.com/userfiles/files/rakivo.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/46835bb66e352053a75040da98c1aef0/69516696739.pdfIn PDF document text
    • https://ladida.asia/sporlegen/administrator/imagetempfile/83238533918.pdfIn PDF document text
    • http://tg-focus.ru/userfiles/files/32270672729.pdfIn PDF document text
    • http://msslink.ru/userfiles/files/runolun.pdfIn PDF document text
    • https://bunyaminerdemir.com/resimler/files/66127960795.pdfIn PDF document text
    • https://mots.alaxarxa.cat/cmsimple/images/file/xagokukezujot.pdfIn PDF document text
    • http://primeasset.hu/fileok/file/kukeme.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/50a0e293dc6c32ea4de72736f5a46b1c/96951204621.pdfIn PDF document text
    • http://anael.fr/fckeditor/userfiles/file/vuluwenakexupibok.pdfIn PDF document text
    • http://telek-trans.hu/editor_up/buzexoz.pdfIn PDF document text
    • https://kcharp.com/ckfinder/userfiles/files/85824020256.pdfIn PDF document text
    • http://studiopol.com/userfiles/files/jedubamabimosagogika.pdfIn PDF document text
    • http://union.travel/ckfinder/userfiles/files/48264490324.pdfIn PDF document text
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/be924aec7cb44cb81a406032f5298a5e/7895094893.pdfIn PDF document text
    • http://www.39koratmachinery.com/file_upload/files/9755960732.pdfIn PDF document text
    • http://k3projekt.pl/uploads/userfiles/files/sozitote.pdfIn PDF document text
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/74e21de5b5355a21f1a17ac96fded8c0/33074008935.pdfIn PDF document text
    • https://bluza-shop.ru/content/File/30006992381.pdfIn PDF document text
    • http://aspbae.org/userfiles/file/98314086280.pdfIn PDF document text
    • http://khojedu.net/userfiles/file/90588189261.pdfIn PDF document text
    • https://rougezenekar.hu/files/file/xosuwusafebilovaxutir.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_off0000c105.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC105 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d91c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD91C 10788 bytes
SHA-256: 1903d634d22bf6da8c133e8e9cc47ad36bf12eaa24b8f9765ebf14a1531cc41c
font_02_sfnt_off0000f1bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1BF 17544 bytes
SHA-256: 5d960c785b6951281ef1bb30ed8008315c7174475ad4740c9658c60f1940b479