Malicious PDF — malware analysis report

Static analysis result for SHA-256 c19c173c4a3eb29a…

MALICIOUS

PDF

69.4 KB Created: 2021-09-05 13:48:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 2736ed31a77507a0bd68cbe32a9f62a9 SHA-1: 0e5872c77eb00b5ab978d60adb418befa9045630 SHA-256: c19c173c4a3eb29ae7868d9ce4ce9d8fc5e6f07122ff98da265cfcbcdbe4088e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised WordPress sites, indicating a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent. The presence of multiple compromised CMS upload links and disposable hosting further supports the malicious nature of this document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/c02682acf39926f616725a795df5a56b/fukaruxixejorejava.pdf In PDF document text
    • https://besi.co/ckfinder/userfiles/files/likuzopobarugonowid.pdfIn PDF document text
    • http://aldo-ins.com/userfiles/file/ponijevemibopowo.pdfIn PDF document text
    • https://gogift-it.com/userfiles/files/27716787960.pdfIn PDF document text
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/liv1npdg2atug7gjlfkgnev0qu/48880002202.pdfIn PDF document text
    • http://bangdientunhk.com/upload/files/3213310111.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/80918676828.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075e9926000e---7886172173.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094b1029ccd9---zenezileg.pdfIn PDF document text
    • http://vamaconsulting.sk/userfiles/file/34440764917.pdfIn PDF document text
    • https://davidfauquemberg.com/home/fauquemb/david/bbdg_site/userfiles/file/85521148743.pdfIn PDF document text
    • http://baikalspring.ru/ckfinder/userfiles/files/66187602545.pdfIn PDF document text
    • https://study4student.com/cache/fck_files/file/somubupetivitenu.pdfIn PDF document text
    • http://watthaistuttgart.de/userfiles/file/nenelomosigevig.pdfIn PDF document text
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/v9sg5s8lgnpe87hcnpef85lclc/mupofufap.pdfIn PDF document text
    • https://radekslodkiewicz.pl/files/file/goxibabokor.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612de98c46bc4---78291886027.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/1fb4c667243f37fb3603cb3112758ab2/40100981957.pdfIn PDF document text
    • http://venusland.vn/app/webroot/img/files/68647893474.pdfIn PDF document text
    • http://emotionpicturesfestival.gr/userfiles/file/41776151722.pdfIn PDF document text
    • https://aful.edu.pe/ckfinder/userfiles/files/15492243052.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/161217fd0b7f22---36755316515.pdfIn PDF document text
    • http://kalmi.ru/upfiles/files/feweragofisubomigavotuk.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=simplifying+exponential+expressions+worksheet+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://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_off0000b051.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB051 14544 bytes
SHA-256: f40a23b06d2b71ad4a13411256b8047289d71ea3038acccc2fc551b804de2d49
font_01_sfnt_off0000d4fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ed11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED11 11416 bytes
SHA-256: 7a97b62570def91b17f8dad59e410b8379519e60c8b2fbc76d6273b3a8b7a4b1