Malicious PDF — malware analysis report

Static analysis result for SHA-256 31a7adcfb2c4c583…

MALICIOUS

PDF

81.1 KB Created: 2021-09-20 19:35:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4a7c4239b70064beb3c6b3071d59cb5c SHA-1: 024879508a84eef246a14e53ae31bf7ae7434e9f SHA-256: 31a7adcfb2c4c583e4a1e5f940e7c62eb2b79cf1a609d1ccb115a41efd01e740
184 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and multiple URLs pointing to compromised websites and IP addresses, suggesting it's designed to redirect users to malicious content. The embedded JavaScript likely facilitates the redirection or download of a second-stage payload. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.5916

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://ketchas.ru/uplcv?utm_term=how+to+install+playstore+in+phone PDF link annotation
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613f22c2c91a5---xenafib.pdfIn PDF document text
    • http://apothepharma.com/upload/files/baxonakajeburubesebewimi.pdfIn PDF document text
    • http://musicpark-live.de/userfiles/file/9620727508.pdfIn PDF document text
    • http://104.156.58.56/~web2inbox/wp-content/plugins/formcraft/file-upload/server/content/files/16147a2919852c---pufumonatigivuxapesit.pdfPDF link annotation
    • http://mwbright.com/upload_fck/file/2021-9-2/20210902191723903085.pdfIn PDF document text
    • http://c2ctrading.org/cms_upload/files/nopaserolobubiwi.pdfIn PDF document text
    • https://villadorottya.hu/uploads/frontend/files/81040882765.pdfIn PDF document text
    • https://cliniquemyo.com/userfiles/file/18773613999.pdfIn PDF document text
    • http://kustari.net/userfiles/file/26242728596.pdfIn PDF document text
    • http://tion.hu/upload/file/61858862432.pdfIn PDF document text
    • http://paliukenas.lt/i/File/pabutigudesibejufunexow.pdfIn PDF document text
    • http://obchodsezlatem.cz/upload/files/47661137877.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/7a98365fc1ea71137be713b7d0f5650c/ritot.pdfIn PDF document text
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/f33257dc634f8ba8f7414ceced85cdc1/nuraxulogelipezunuzim.pdfIn PDF document text
    • http://animalscipublisher.com/files/upfiles/file/1824415485.pdfIn PDF document text
    • http://upoart.com/ckfinder/userfiles/files/gajugu.pdfIn PDF document text
    • http://wccflooring.com/userfiles/files/31765424814.pdfIn PDF document text
    • http://huichem.com/ckfinder/userfiles/files/fusokosaruwovukexit.pdfIn PDF document text
    • http://hefei.chinatupai.com/web/js/ckfinder/userfiles/files/49710945460.pdfIn PDF document text
    • http://ozanatalan.com/iboard/includes/userfiles/files/17980330382.pdfIn PDF document text
    • http://dansensvenner.dk/imagesfile///nagufedu.pdfIn PDF document text
    • https://shreenatharcade.com/userfiles/file/92201001703.pdfIn PDF document text
    • http://kapsalonindex.nl/images/uploads/84654175295.pdfIn PDF document text
    • https://pushtypathshala.com/demo/aims/files/images/files/48460098649.pdfIn PDF document text
    • https://hometutorsdelhi.com/userfiles/files/benijifowegusej.pdfIn 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_off0000e104.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE104 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f916.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF916 18460 bytes
SHA-256: e9dc7e631b956178d7015fd11b1b94b0d47cc54370fd3a3a7cf72320b9b3468f
font_02_sfnt_off00012882.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12882 10540 bytes
SHA-256: 18a7020314adb28000a86af01b1ce79f9f5a80281232e24ec6341b23b8763056