Malicious PDF — malware analysis report

Static analysis result for SHA-256 7335569ac3b9bf71…

MALICIOUS

PDF

92.8 KB Created: 2021-06-29 00:19:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 651b6c93688f916decd47b6112405353 SHA-1: 5f4f4ead63dd90aa154c9e78d8f80bc0426100de SHA-256: 7335569ac3b9bf713a75d4e96fd92432254887e62e31d9951f8b5e12c25e7639
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is often used to exploit vulnerabilities or redirect users to malicious sites. It also features a link farm pointing to multiple distinct hosts, including a compromised WordPress upload directory, indicating a phishing or content-luring attempt. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://tubietelbar.hu/uploadfile/rawalotib.pdf In PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/91166729969.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/16086200608371---41958516292.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160855327464a0---56882343053.pdfIn PDF document text
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/cebo2o3ks75gqvb9nmagfhaa7o/40155698432.pdfIn PDF document text
    • https://hirurgija.me//files/95759370475.pdfIn PDF document text
    • http://studiozammuner.eu/userfiles/files/52697664500.pdfIn PDF document text
    • http://veiligheidssloten.nl/ckfinder/userfiles/files/vuzope.pdfIn PDF document text
    • https://www.axelendinggroup.com/wp-content/plugins/super-forms/uploads/php/files/38e868659684fc2018546791b3c7cc4f/95244719591.pdfIn PDF document text
    • http://cogersquest.com/clients/f/f6/f6194b381802d71b6842d6160e8859b1/File/30294424793.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc235af716---77857163686.pdfIn PDF document text
    • https://humicdp.com/uploads/2021-06-17/images/files/24586698080.pdfIn PDF document text
    • http://skyrunarser.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/2106071548538058691sf0ks.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/160ae8b37893ce---35097955908.pdfIn PDF document text
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/d7132190cb998cde4cb255f66571b79f/92290563623.pdfIn PDF document text
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/3ce73362bf96c58892243a0ebdec45c1/60958566271.pdfIn PDF document text
    • https://abeess.com/userfiles/file/dobafovewezez.pdfIn PDF document text
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607507186ee9a---mirunejevekuwexabaji.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///litadomarisuritalezoma.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/7b876af18ab25e80cc9b9c2f93cc6dc4/16190995345.pdfIn PDF document text
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b489e1202c9---63604493781.pdfIn PDF document text
    • https://banghenails.com/upload/file/30675811683.pdfIn PDF document text
    • http://cutencuddlybreedables.com/_images/file/tisagoradiwepixebani.pdfIn PDF document text
    • https://study4student.com/cache/fck_files/file/lumuzigorok.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5372587cf---kakazajeratozobor.pdfIn PDF document text
    • http://ilovechardonnayhills.com/userimages/nixep.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=the+sheltering+sky+book+pdfPDF 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://copland.udel.edu/~jbaling��������������������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_off000104ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104AB 10924 bytes
SHA-256: d195270cdf619cba0dacbaf9f8c3db8a8a3b67a83869e3df81d34a2c6488512e
font_01_sfnt_off00011d81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D81 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013593.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13593 17776 bytes
SHA-256: 3a9dda4e06fd59cccf6767c9b020041c6c5aca1360351e826389adca5750871d