Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf8d20b0a514a2bf…

MALICIOUS

PDF

82.2 KB Created: 2021-10-12 18:45:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 190b9e0501b02d2b9c3596300e924fa9 SHA-1: 10961861e1a354a31a11b1f78e51be943ef2590b SHA-256: bf8d20b0a514a2bf309e4d9b750709a53f17b39dba4921d1148e45d6d5f1eec3
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised or suspicious domains. The presence of numerous embedded URLs, many pointing to sites with file upload functionalities, suggests an attempt to distribute further malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 https://clubsecurite.fr/webroot/upload/files/mobawaraz.pdf In PDF document text
    • http://canvangdientu.com/images/file/12651935683.pdfIn PDF document text
    • https://asi-filter.pl/files/file/runanino.pdfIn PDF document text
    • http://tikatalog.sk/_files/file/26692505521.pdfIn PDF document text
    • http://rassadaspb.com/new/files/file/92597923753.pdfIn PDF document text
    • http://bocghebinhduong.com/media/ftp/file/romewimefirerunemibunad.pdfIn PDF document text
    • https://www.cascatai.com.br/ckfinder/userfiles/files/13838827596.pdfIn PDF document text
    • https://turismo-galicia.es/ckfinder/userfiles/files/weferevokafodafisudimoso.pdfIn PDF document text
    • http://quesnelfoundation.ca/userfiles/file/91502368547.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/0q0kf3h31tc1tm30spv8v0j14b/rutexobifitunema.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/82250474468.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/16140e12f4be9f---vakapizivisuvanuxivid.pdfIn PDF document text
    • https://vnjhanoi.com/upload/files/rebujamalaxupulelefebeb.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/5d57b61c851dce428eb969721b8079c3/linobujefifalidaba.pdfIn PDF document text
    • http://artecgroupservices.com/imagenes/file/vakux.pdfIn PDF document text
    • https://brothers-music.com/ckfinder/userfiles/files/3427736775.pdfIn PDF document text
    • http://tangiahoang.vn/Images_upload/files/96444427305.pdfIn PDF document text
    • https://aquaprosmart.com/userfiles/files/biwasuxetajemo.pdfIn PDF document text
    • http://uniquehotelsolutions.com/files/others/wefebefaremufibujises.pdfIn PDF document text
    • https://srilangkapools.com/contents/files/barepikiw.pdfIn PDF document text
    • https://dalycity.com/wysiwygfiles/file/32053350737.pdfIn PDF document text
    • https://rdsdealers.com/ckfinder/userfiles/files/gunuzubum.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/896FEnmJZlk/uplcv?utm_term=trees+in+monet+paintingPDF 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_off0000db28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB28 18748 bytes
SHA-256: 6f05efc54d13c08d1c1cb2dc985a8889728f285b6b84aba44cb12c121dc6f5a5
font_01_sfnt_off00010b8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B8D 10512 bytes
SHA-256: 440063e4298243664ce72b722d9bee05c103ca9577f341a2f383c54a61b39f96
font_02_sfnt_off0001237c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1237C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1