Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf1dbd3f54321124…

MALICIOUS

PDF

96.6 KB Created: 2021-09-21 22:11:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 6d6a0752e1801b6c24bad52ccd4a684a SHA-1: 04fe1803843bb16cd0e9cc0741f059d384297fb9 SHA-256: bf1dbd3f54321124db9becf315a04c84daf7bfbdb8d0be4e17e1b991efeda5d0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier. It contains a link farm pointing to compromised WordPress uploads and other disposable hosting, suggesting an attempt to distribute malicious content. The presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution attempt, likely leveraging a spearphishing attachment vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/681b4e6737f532c8a3b88f57b1c20905/8403863984.pdf In PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c4c92db15f---84243514528.pdfIn PDF document text
    • https://madeinstlucia.com/userfiles/files/jokisakabisaru.pdfIn PDF document text
    • https://cs-nippon-cp.com/mailmagazine/upload/files/70324417637.pdfIn PDF document text
    • https://samarthanamparisara.org/apadmin/uploads/userfiles/files/jesusevoxotix.pdfIn PDF document text
    • http://aromacosmetics.bg/assets/userfiles/file/26861418268.pdfIn PDF document text
    • http://pokwuttibut.com/file_media/file_image/file/44278324485.pdfIn PDF document text
    • http://humidorio.de/ckfinder/userfiles/files/migilumepevesikubigiva.pdfIn PDF document text
    • https://wintechindia.in/ckfinder/userfiles/files/naxakidifitewekaboviwur.pdfIn PDF document text
    • http://napiarsaigh.com/images/guwapodagamaweluxu.pdfIn PDF document text
    • http://brmxn.com/userfiles/file/20210901080100_ke4h00.pdfIn PDF document text
    • https://bandotrading.it/uploads/file/74830832859.pdfIn PDF document text
    • http://a1-automotivegroup.com/upload/files/sugagojoxetolamet.pdfIn PDF document text
    • https://navliecky.net/userfiles/file/22299935326.pdfIn PDF document text
    • http://osmed.cz/app/webroot/files/files/pifijodo.pdfIn PDF document text
    • http://moiarchitekci.pl/pliki/file/17413159239.pdfIn PDF document text
    • https://limadelimon.com/images/file/97902206736.pdfIn PDF document text
    • https://briljant-maleri.se/UserFiles/files/18298635153.pdfIn PDF document text
    • http://ptktent.ru/userfiles/file/1290778885.pdfIn PDF document text
    • http://vattuxaydunghl.com/userfiles/file/33101383075.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612fc58d346c3---43177034821.pdfIn PDF document text
    • https://raljob.com/userfiles/file/24665867630.pdfIn PDF document text
    • http://www.skk.com.hk/admin/ckfinder/userfiles/files/76796843786.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161328e426e5fc---8089059414.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=download+final+fantasy+tactics+androidPDF 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_off00010ad9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AD9 21636 bytes
SHA-256: b1557a418e8e415d18fea2fb01d96054d6f7ea1970bb88f625c5b5b60d84eda1
font_01_sfnt_off00014455.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14455 10540 bytes
SHA-256: db7dd4b7e82bcafb2a13e88776fbabb6556870c3e04bb7caff1e2477a38f4095
font_02_sfnt_off00015c8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15C8A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1