Malicious PDF — malware analysis report

Static analysis result for SHA-256 97dea9a9c4c843a5…

MALICIOUS

PDF

85.4 KB Created: 2021-05-06 21:34:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 17058193060c97171a260ad560f9030b SHA-1: b5b11f1b7188fa65ea762e83c428724fc7a2d194 SHA-256: 97dea9a9c4c843a56c7b9291ba259b41502865f4eb2039f71e8f9241879717ce
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a link farm or redirection mechanism. The document body, though heavily obfuscated, contains text related to 'promissory note template', indicating a potential lure for phishing or malware delivery. The ML classifier strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://begemot-rus.com/uploadfiles/file/2021042908323673499.pdf
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607f14979f306---kipexax.pdf
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085954c7b584---34101974761.pdf
    • https://www.hemoroidklinigi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cadfa86feb---vifetafot.pdf
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076066a5c0d8---dofiraz.pdf
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/275db71436c5194b5434ecc005c23a56/bozuxul.pdf
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16088f1deb80c3---tekuvokozogi.pdf
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608581abb9c1b---pekizuvazizatupi.pdf
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/369elhll19acl5fvds5c2qm7km/dopiputurinebapewepobawi.pdf
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/160799d4c96f72---vekukekositatowalavozo.pdf
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082561e13e87---26372547363.pdf
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080d8da04215---mimubazirovilepil.pdf
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/16076c4592aaa8---pubudi.pdf
    • https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/3f3cab90c0a5e23638d66786e8d14132/lavepifura.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16074494607088---dipirajodilepa.pdf
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/c93f2879940a4f0f119f70d5429d07d3/lazas.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=promissory+note+template+bc+free
    • 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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010ca3.bin
08ff0c146f534e9dbd1851f596d0b825ee70d6fcce962074bfa3772825931a7b
pdf-font-stream PDF embedded font (sfnt) at offset 0x10CA3 5404 bytes
font_01_sfnt_off00011ef2.bin
a60c0e669aaad27191cb53bbe46ddc514d3a6552f29b95a0709e64c5efc0b4c1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11EF2 11732 bytes