Malicious PDF — malware analysis report

Static analysis result for SHA-256 ccf5c4257dfc55c5…

MALICIOUS

PDF

84.9 KB Created: 2021-06-28 06:01:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: bcf4f5e8afa92501a9e01fcd3eeebe7f SHA-1: 2293c1b720970c61562e56560e5239936721d081 SHA-256: ccf5c4257dfc55c52ab8c07144851690388b5f59c9f716dfb25bfbf5792f186f
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier, indicating it likely contains malicious content. The heuristics reveal it functions as a link farm, pointing to numerous compromised WordPress upload directories and other disposable hosting sites. The primary purpose appears to be directing users to potentially malicious content hosted on these compromised or untrusted domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://bacviettech.vn/userfiles/file/jitorenodup.pdf In PDF document text
    • https://endoaccessories.com/wp-content/plugins/super-forms/uploads/php/files/5in5k3niao3gehn43dq61ph5n4/sumatuvezanafekato.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c08347c71f2---84700370772.pdfIn PDF document text
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e9ee719f89---30943535686.pdfIn PDF document text
    • https://delphin-bau.com/ckfinder/upload/files/gipegu.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607621186b020---lijudusur.pdfIn PDF document text
    • http://malbreil.com/userfiles/file/69263010035.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b5a03726e12---40720895606.pdfIn PDF document text
    • https://qualitylightsolutions.com/wp-content/plugins/super-forms/uploads/php/files/cd31fa2f87c91c559a84c91ec0c9610d/bikidelibubujoda.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ab8751cf75---rudepabenagefosegile.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b17a0eee476---92150822194.pdfIn PDF document text
    • http://fsoa.cn/userfiles/file/1240708216.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4f28e60e8b---59041931704.pdfIn PDF document text
    • http://lorichphoto.com/pictures/file/nozived.pdfIn PDF document text
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/0283eead2cacbe6e6e3217cbd3428067/xipig.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/160763cb830421---tamupuxuvubiwidogoxuxafed.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac4125caa9c---74510222796.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a58b6978d24---77472089504.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca34c2b559---damirenelifunakivitu.pdfIn PDF document text
    • http://drstevealbrecht.com/wp-content/plugins/super-forms/uploads/php/files/447c382eb09833f025616e470cd68549/jipugefek.pdfIn PDF document text
    • http://ccswcd.com/userfiles/file/kodasimeliri.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/69b802faae23da823f08f403091de2f3/sutipinifikafiwuza.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088f6c5b4610---xujovam.pdfIn PDF document text
    • http://ingmontagna.com/userfiles/files/11641042471.pdfIn PDF document text
    • https://www.hausbootgeiseltalsee.de/wp-content/plugins/super-forms/uploads/php/files/tsgt84nodmdbng7ba7mrebft8u/xufumemaxofogidimibe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=cell+parts+and+functionsPDF link annotation
    • 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_off0000ea26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA26 16880 bytes
SHA-256: fd9ce50aa3eaed8cab4921792d84dc5f698ff3c03e7bb1cbf0a377f3d1a80503
font_01_sfnt_off00011566.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11566 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012d7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D7D 10744 bytes
SHA-256: 5280a2406779c625570975c503fa3a71a1a71ea85a8dabf3da73c652900b0282