Malicious PDF — malware analysis report

Static analysis result for SHA-256 ffa854be26e9f966…

MALICIOUS

PDF

82.6 KB Created: 2021-09-03 01:45:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 5be2bd8a59f3a6489a5151d7d13f6c30 SHA-1: 62ddb50434dc882fe1ef3aa2e1dc8699160f2cbd SHA-256: ffa854be26e9f96616ac4356aab375f24324e5b3bfa8e9f5ad64480b66b4a763
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on various domains. Several heuristics indicate this is a link farm, with some links pointing to compromised CMS upload storage. The ML classifier strongly flagged this PDF as malicious, suggesting it's part of a distribution or redirection chain.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • 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://paliukenas.lt/i/File/xusewukaxitawunofen.pdf In PDF document text
    • http://sity-luxe.ru/userfiles/file/supilovana.pdfIn PDF document text
    • https://vetamblj.si/ckfinder/userfiles/files/latibipolefum.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070fb62301b1---pegusela.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/4sm6440qk3fslitmji4jn5mttf/wabagiwulukaxivodokotafix.pdfIn PDF document text
    • http://studionegro.net/userfiles/files/41539202659.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/eef64a3a1f3ad99efec59a2d27b20aa1/fitaduronepexumumejotu.pdfIn PDF document text
    • http://bloemenwinkelindex.nl/images/uploads/tiwarobutojowe.pdfIn PDF document text
    • https://almuhja.net/ckfinder/userfiles/files/lamegoni.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607886171559e---gowat.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609cb5c0a0bd5---8397713636.pdfIn PDF document text
    • https://xn--fiqa735be48e.com/upload/files/guxojigovarafuwuwutubode.pdfIn PDF document text
    • http://519pf.com/userfiles/files/mosepi.pdfIn PDF document text
    • http://freetourscadiz.com//ckfinder/userfiles/files/23283511561.pdfIn PDF document text
    • http://cainghienbinhduong.com/uploads/userfiles/file/86533970857.pdfIn PDF document text
    • https://zapcdn.space/web/img/podborky/files/xitaxagelutulirevikelapa.pdfIn PDF document text
    • http://angelescare.com/userfiles/file/48062874560.pdfIn PDF document text
    • https://costabravas.com/uploads/localidades/files/jeketipugaxivex.pdfIn PDF document text
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091ba06b0c4a---bolepom.pdfIn PDF document text
    • https://sim2007.com/files/5544604394.pdfIn PDF document text
    • http://mastrodibaglio.it/userfiles/files/titudimujezaxuw.pdfIn PDF document text
    • http://scro.ru/pic/file/gibimukofif.pdfIn PDF document text
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160988d5c72543---samuwezesivimofen.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16077becd4185f---zesafafedetikapema.pdfIn PDF document text
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/52c08060a0a1672bcdc2795b964ce0e7/91356501885.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=non+criminal+affidavit+tcs+pdfPDF 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_off0000dd45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD45 10692 bytes
SHA-256: b6369b98e1c9f9c74017bda04d8a34f164dcd4724b7ae642753826b25c2fc383
font_01_sfnt_off0000f5c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5C9 18296 bytes
SHA-256: a93471f10f4baf1f5275d181331f6740f9e6a9275eb56380740e32a1e66b9c04
font_02_sfnt_off00012504.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12504 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1