Malicious PDF — malware analysis report

Static analysis result for SHA-256 427b74f75d13ac12…

MALICIOUS

PDF

91.5 KB Created: 2021-07-21 12:05:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0245cb8753ae1edadb405bc4276cbcb6 SHA-1: 2384163e5a3e43d9159b433bef6ec3a946fee7ba SHA-256: 427b74f75d13ac1299a30ebfa83247139ec2445717ff1c6f2c3034d4909098e6
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple potentially compromised or disposable hosting sites. The presence of numerous external URIs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly suggest a phishing or malware distribution scheme.

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://caudafotografia.com/userfiles/files/jetukunivuva.pdf
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/41b4a2c70bf875fe4168ff7dba83ec6c/xabedarifapor.pdf
    • http://absolutelyneon.com/userfiles/file/ragerunosagubepig.pdf
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fcc26b85ea---99244161593.pdf
    • http://stadiumhighschoolclassof1965.com/clients/0/00/0080f9a3d0f10e930bcfc39f0a940e94/File/lotupinutivopaxiwedewojav.pdf
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/2367e1084ce265a5193820daa79b87f7/leseminine.pdf
    • http://studiotecnicodama.it/userfiles/files/bubezak.pdf
    • https://fishuntpesca.it/file/momoludexamadurudagokujo.pdf
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160afca572ba06---97155501579.pdf
    • http://cheers-gifts.com/userfiles/piketemuvisuf.pdf
    • http://szpitalstrzelin.pl/userfiles/files/lazadu.pdf
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/5okegcvgr5qhtih9l6frneq41k/xikujanilomi.pdf
    • http://www.corazondelsol.es/ckfinder/userfiles/files/mirajobusukifokasiririj.pdf
    • http://hungbuloon.com/media/ftp/file/30861966316.pdf
    • http://coxfamilyreunions.com/clients/5/56/566bc9ad745482f371977770c3e6b383/File/58454937828.pdf
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a258d1b42c6---vimojozoxenoxujatawumovi.pdf
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/05d3bea455d13b2927467e9037a8a7c1/78972541979.pdf
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ed2af09f9f---33934763520.pdf
    • http://oprfhs70.com/clients/879438/File/78080473022.pdf
    • http://bitite.lv/media/txt/122/file/53772514703.pdf
    • http://asianaccounting.com/admin/fckeditor/userfiles/file/wifutez.pdf
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c0f3b2d54b0---83175177128.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=z+table+that+goes+up+to+6
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000103d7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x103D7 16792 bytes
font_01_sfnt_off00011bee.bin
1131fcdcea798ea099cc8a58c9382da446b39f6d80fa99e9e8b1bdc479b82ee9
pdf-font-stream PDF embedded font (sfnt) at offset 0x11BEE 10604 bytes
font_02_sfnt_off0001342c.bin
ae17df76434979dd81becbd515c455775a7dc89ea7986918ba76c05b94923c19
pdf-font-stream PDF embedded font (sfnt) at offset 0x1342C 17124 bytes