Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bf16b668ea98fcf…

MALICIOUS

PDF

83.4 KB Created: 2021-09-08 00:08:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: e0075c0a5697efabdbc43ae038f47bb8 SHA-1: 28c1ae5b90a8f91e29a51c7ea5fd2a3a89738777 SHA-256: 4bf16b668ea98fcf17b7aafe08f0ab2e94a0c1bfefaddc94536327bb140305f4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable hosting, suggesting a link farm or phishing lure. The PDF structure and embedded links are indicative of a phishing campaign, likely using a spearphishing attachment as the initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://morpheus-architects.com/file_media/file_image/file/923509506.pdf In PDF document text
    • http://e-hane.com/files/puwijikad.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608e6134796b6---78076356739.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/1797e1416741abd34fe0c3eff4fe5406/semeni.pdfIn PDF document text
    • https://quaint-house.com/images/blog//file/vosuk.pdfIn PDF document text
    • http://theettiaresottawa.com/clients/e/e8/e8f54e69a7463df9fd0adff13cd8e90f/File/sofexenesexabotige.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079ec055b4e9---bidilivilimotadafixewuvaw.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc527532f56---lofidujujepifepuv.pdfIn PDF document text
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/40mb9frsbf8pmto5ktfpaqvu8c/35852544947.pdfIn PDF document text
    • https://www.spitalmoldovanoua.ro/ckfinder/userfiles/files/bufenimo.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612554cc14f0e---sekeloberedidaxovejef.pdfIn PDF document text
    • https://www.reflectionuk.com/wp-content/plugins/super-forms/uploads/php/files/i1cirnb1e65gl00v3ncfa05mc0/31730996614.pdfIn PDF document text
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607e0ef00054c---wukegenobaregudodase.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/24gbq4b96lo2of4dpfqkpruope/gujibokupepup.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/6c76c6d1fed9ad717bdb4c068c52ff96/lafodogazodus.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161257adb6c8b5---55180233718.pdfIn PDF document text
    • http://fulepmark.hu/nyebu/fulepmark/userfiles/file/83140064143.pdfIn PDF document text
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160ee54e50ebf8---18692143532.pdfIn PDF document text
    • https://dichvumayphoto.vn/webroot/img/files/43482881426.pdfIn PDF document text
    • http://globalquestconsulting.com/userfiles/files/pivifekewixugiworeso.pdfIn PDF document text
    • https://www.servicioscalibrados.com/wp-content/plugins/super-forms/uploads/php/files/a826df284c00fb32892d8d20b9bd76ec/pewujax.pdfIn PDF document text
    • http://bassbasement.org/userfiles/file/82853505926.pdfIn PDF document text
    • http://ikcem.org/userfiles/file///varuxikojoworetezexa.pdfIn PDF document text
    • http://rafaelokazakov.com/file/65305561102.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=learning+basic+chinese+language+pdfPDF link annotation
    • https://youtu.be/gjyxmfvIn 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_off0000e091.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE091 10880 bytes
SHA-256: 1f50f5d4b51bbe815aa7531ca03b3901d0d9912f93cdb32a3af8d7e7d26b2b15
font_01_sfnt_off0000f928.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF928 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001113a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1113A 18048 bytes
SHA-256: d4225545dd465bd3632ed74d20d47d1014a66ba57c518e9c91cc67106598901c