Malicious PDF — malware analysis report

Static analysis result for SHA-256 c67acb5873d26281…

MALICIOUS

PDF

87.4 KB Created: 2021-09-16 16:27:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 08520af6683480f4150b545a5d58e8e6 SHA-1: b17626f213a9f98a629219ec8dca76ae059fbe98 SHA-256: c67acb5873d2628140d168b3e7608854d148ecfa640f847f8fb6b878baf1801e
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. The file contains a link farm with numerous URLs pointing to various domains, many of which appear to be compromised or disposable hosting. These links are likely intended to redirect users to phishing sites or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://krisoc.ru/uplcv?utm_term=audio+editing+software+android PDF link annotation
    • http://akcjonariusz.com/UserFiles/file/tevufujelixatuwo.pdfIn PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/161405b2ae5527---10616978414.pdfIn PDF document text
    • http://esllearningbydesign.com/app/webroot/files/file/kibukipelazipiwoja.pdfIn PDF document text
    • http://elitsatodorova.com/uploadfiles/file/besevisamebot.pdfIn PDF document text
    • https://micsys.in/userfiles/file/92395717285.pdfIn PDF document text
    • http://midesignvn.com/uploads/files/faveremumopugifujuw.pdfIn PDF document text
    • https://pasationtravellers.com/root/FCKeditor/file/ludetowifekafe.pdfIn PDF document text
    • https://godparents4tz.org/home/god/public_html/ckfinder/userfiles/files/94910699767.pdfIn PDF document text
    • http://kelsenator.com/userimages/23834692021.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/16134476e8f008---20634173079.pdfIn PDF document text
    • http://cichanski.com/Upload/file/31655033267.pdfIn PDF document text
    • http://pokwuttibut.com/file_media/file_image/file/zovekovojonapilura.pdfIn PDF document text
    • http://praguynakorn.com/praguynakorn/picture/datapro/files/89121148649.pdfIn PDF document text
    • https://fishboat.hr/files/fewogidub.pdfIn PDF document text
    • http://ke-sen.com/userfiles/file/1631349908.pdfIn PDF document text
    • https://bitree.ru/ckfinder/userfiles/files/zuferupiretuwuriza.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/tnv0nec1indltgmp0t362v20j6/rugijiputunowaxa.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135202d88ce8---zuludutajusanal.pdfIn PDF document text
    • http://mikomisushi.com/uploads/files/dukavoxokubo.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/6e8c7a7273983fb891c3b2cc112a2658/kuravurikoraxorog.pdfIn PDF document text
    • https://samsungvrvklima.com/upload/ckfinder/files/93621011858.pdfIn PDF document text
    • http://modern-pro.ru/files/file/44109093661.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/bifizovepifavoripoxap.pdfIn 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_off0000f145.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF145 10652 bytes
SHA-256: 81cd6dad1b10af3779c7b1dc4a7052c7504910562105617882c6a3ee58a7fb54
font_01_sfnt_off000109a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109A8 17808 bytes
SHA-256: 420ebdef033f1386de1ca36c1bc138de7eec8baa613a03a3fb1da7cd5767b333
font_02_sfnt_off00013788.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13788 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1