Malicious PDF — malware analysis report

Static analysis result for SHA-256 b42cba1b91ba4679…

MALICIOUS

PDF

70.9 KB Created: 2021-09-04 22:49:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8d6c21efccd736b009094ea2ff42297c SHA-1: b464385bf22c405e3ff5b9ff8d44fbdc1dd44aec SHA-256: b42cba1b91ba467911a7982527c52bdf3605683a342c6277b32ee96445165671
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document contains numerous links to external websites, many hosted on compromised WordPress sites, suggesting a link farm or phishing lure. The ML classifier strongly indicated maliciousness. While no scripts were directly extracted, the presence of embedded URLs and the nature of the heuristic firings point towards an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://huntic.ru/uplcv?utm_term=converter+pdf+para+dwg+free+online PDF link annotation
    • https://www.northernillumination.com/wp-content/plugins/super-forms/uploads/php/files/fe56a26ff42fcc0e5f117c9a2bd2f582/lijutopesaja.pdfIn PDF document text
    • http://smeclassof1987reunion.com/clients/37165/File/josafetilapiluji.pdfIn PDF document text
    • http://myqself.com/upload/files/50199648226.pdfIn PDF document text
    • http://hk-dcc.com/wp-content/plugins/super-forms/uploads/php/files/5faatgs7c9gqpht9q49k1f91tk/17322999839.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160851e7b42d7c---malepegadomojirowijelon.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607de4f18a25c---13708592793.pdfIn PDF document text
    • https://misionesmedellin2030.com/wp-content/plugins/super-forms/uploads/php/files/9koej7sooied9q46ckbmc07avm/6502196518.pdfIn PDF document text
    • http://www.heksan.com.pl/file/pirib.pdfIn PDF document text
    • https://dimensionshoppe.com/alpha/ckfinder/userfiles/files/44144225045.pdfIn PDF document text
    • https://webmenuplus.com/images/file/14918882289.pdfIn PDF document text
    • http://mea-travel.pl/userfiles/file/96442485229.pdfIn PDF document text
    • https://aspaeng.com/files/image/files/rivavez.pdfIn PDF document text
    • http://canvangdientu.com/images/file/xigipujefofi.pdfIn PDF document text
    • https://okinawa4d.com/contents//files/47146317669.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1612714ac2c020---nufaxelosomote.pdfIn PDF document text
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160da6d472b59f---27951221846.pdfIn PDF document text
    • https://upbilbao.com/ckfinder/userfiles/files/tukemoxuxajoj.pdfIn PDF document text
    • http://ihvanturizm.com/rsm/files/woputofozulafuz.pdfIn PDF document text
    • http://gernano.eu/gfx/userfiles/files/fubavipeso.pdfIn PDF document text
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/2a911db29e5cda5259546e31de5c0804/jovipatuzoxe.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/ebaa02a191960d75d582551821f9406b/biwevaxipogiku.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/181905516113.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609643af03ed0---nogisadupigunedutewopi.pdfIn PDF document text
    • https://llibreriaha.com/img/events/file/mokuzurezitavab.pdfIn PDF document text
    • 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_off0000b724.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB724 15000 bytes
SHA-256: ceb411319b751dcb528825bc092e3a43beeee24e5e5c37def6998940a4284702
font_01_sfnt_off0000dd4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD4C 10688 bytes
SHA-256: 805816fa4033d055a457235fa046b5a51032d0b9aeb7e70910108f7cacffe0af
font_02_sfnt_off0000f5cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5CC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1