Malicious PDF — malware analysis report

Static analysis result for SHA-256 b35f33fb8fefce5e…

MALICIOUS

PDF

89.1 KB Created: 2021-06-26 12:25:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b2fab043814ca4fa2f9c39c410706fa2 SHA-1: c72a871d977ce068b9e450cf5f50e6ff6f0eabac SHA-256: b35f33fb8fefce5ec01346e943aa5c0019d858378dcc7a2f0b0d0f0ca5a632ba
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous URLs, many of which are hosted on compromised WordPress sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable due to its binary nature, but the heuristic findings are sufficient to assess its purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/vgi5cjcslva0ftvm86q618nbh4/96428454147.pdf
    • http://manavpublicschool.org/manav/userfiles/file/84836475002.pdf
    • https://angelsstaff.com/uploads/file/88552671289.pdf
    • https://patoman.ro/ckfinder/userfiles/files/pesiganakus.pdf
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160bb0ab5d57c0---xerisex.pdf
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/98cde99fd37b7c9720a5b218b737c922/nojitavakawejomoveteribe.pdf
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/2eb984f6e3969bf15987aabe1eabab06/fiwexez.pdf
    • http://clear-es.net/yamituki-n/uploads/files/konebelonux.pdf
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/2eef978197a1afbf1533c9eeaa71ddaf/kuxanalugikivok.pdf
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/e63a88888758440e4a26fdba06f07e6f/dadejenizebitunemipererom.pdf
    • https://perfecthospital.net/FCKeditor/file/dumanuboruw.pdf
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/83f0b4ae64a6811709cb243501d78104/95509948561.pdf
    • http://abacusnancy.com/userfiles/file/bujalil.pdf
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d358b216309---xuwurov.pdf
    • http://alkanboya.com/files/file///53839779109.pdf
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/160843d8701b0c---vubaniw.pdf
    • http://hzdsbg.com/uploadfile/1620600364.pdf
    • https://securityguardsupply.org/php/uploads/file/zuvozokijususotegimovudu.pdf
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160ab19b5c4b3f---31726492481.pdf
    • http://lt101shop.com/userfiles/files/76686467998.pdf
    • http://linkingpeople.info/userfiles/file/72220024453.pdf
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fedd30856d---23898649765.pdf
    • http://thehawthornnyc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160777dfb8b58d---29565302101.pdf
    • https://mytopics.it/uploads/file/80696162716.pdf
    • http://mutitar.com/user_img/files/vanexeloxisaka.pdf
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/90dbb024bea691c2d51a99741d7e5dc6/xuxuxagugejoxoxup.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=minecraft+java+edition+download+free+for+laptop
    • 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_off0000f7d9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7D9 16792 bytes
font_01_sfnt_off00010ff0.bin
541357024b722dd7e401dda7fd34879823bfad47658d194278ef06a7cb3e1b32
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FF0 10720 bytes
font_02_sfnt_off000128b0.bin
0deb1c630ade0a6cc88716c33f399d923c1f4409514e51c0bff97a96de4667ee
pdf-font-stream PDF embedded font (sfnt) at offset 0x128B0 17524 bytes