Malicious PDF — malware analysis report

Static analysis result for SHA-256 16c3bdb489db8bb1…

MALICIOUS

PDF

84.1 KB Created: 2021-07-03 06:44:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 472587fc3b9db4ee40b8c236595b6456 SHA-1: 66a9a0f19d825ca211fa01112810fe5e35501d42 SHA-256: 16c3bdb489db8bb19cfef60d4724f14858385fe5f2fadfaf522091032773f518
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites. Heuristics indicate these are part of a link farm, likely designed to lure users to malicious content or phishing pages. The ML classifier and ClamAV detection strongly suggest malicious intent, classifying it as a phishing trojan.

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 https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/en0bljppf4n3frdfdhdhk35c3c/54927058274.pdf In PDF document text
    • http://mmbc.cz/_data/user_files/file/18881372847.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3b40351a2---buwurinemomotafilenepamaj.pdfIn PDF document text
    • http://duda-tech.pl/dudatech/upload/file/nagogusebefu.pdfIn PDF document text
    • https://topplene.com/upload/ckfinder_temp/files/20210611123106.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609f5fbf117ad---lazoliv.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a90f84b787b---diwaf.pdfIn PDF document text
    • https://hogies.com/includes/template/uploads/file/xumojevanoxoratoxelunabe.pdfIn PDF document text
    • http://jun-travel.com/userfiles/file/beremorumi.pdfIn PDF document text
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/e82bf965fb040b4e5473c74366cb7ce6/14559426419.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cdf4a19528---fujorejodugukesijin.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d695ad6d4cb---vazalowiluwopiredanoro.pdfIn PDF document text
    • https://poolpoint.be/uploads/file/99588144419.pdfIn PDF document text
    • https://capitalsyndic.com/userfiles/file/62103191426.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cac92a87dba---71965888733.pdfIn PDF document text
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607cd8d59ac7b---63800827494.pdfIn PDF document text
    • https://www.zulilighting.com/wp-content/plugins/super-forms/uploads/php/files/498d93e88ed05938322725d3e1226524/74797865487.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/1609024d710b74---9017246192.pdfIn PDF document text
    • https://www.temsilcifirsatlari.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078c4984e7b3---15298343889.pdfIn PDF document text
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/f7dc2d39b26d515a213d074dd7d62687/fitiwofakopozagosa.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607749f786258---34381209271.pdfIn PDF document text
    • https://eandjfamilyhealthcenter.com/wp-content/plugins/super-forms/uploads/php/files/9c108e26724f6d2a265e3f79f90c93ab/xogidiz.pdfIn PDF document text
    • http://transsnabstroy.com/userfiles/file/savawokajabevo.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a180297c6a1---97618693614.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=how+to+make+an+afk+mob+farm+in+minecraftPDF 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_off0000e56b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE56B 17488 bytes
SHA-256: 9e992f68697d1456ad82e06c449ce281c419d2c60f6ec90972d00109fe0561e7
font_01_sfnt_off000112ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112AE 10592 bytes
SHA-256: a6ee535b3fee2c6175b7ff52b06f9e4112c74be85f1a76f196ad6115f1f1dce0
font_02_sfnt_off00012ae3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AE3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1