Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8c86cd8e500a844…

MALICIOUS

PDF

80.3 KB Created: 2021-09-03 07:51:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b168bf053985c15ecf0755156c54d96b SHA-1: 33b454b39ec97468263f21e55b18a432f1dd6394 SHA-256: b8c86cd8e500a844a59110fe8d11eb837fb324465905921e967e529bfbe10901
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting it functions as a link farm designed to redirect users to malicious destinations. The 'SE_INVOICE_LURE' heuristic indicates a potential phishing pretext, and ClamAV detection confirms its malicious nature. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/d28870ea279bfc2d3e534d304deb5f0e/11632003763.pdf
    • http://namngonviet.vn/user-/files/27787995698.pdf
    • http://studiovalecchi.it/userfiles/files/36580277602.pdf
    • http://maychamsocda.vn/images/userfiles/file/japize.pdf
    • https://chandrakantmusicacademy.org/ckfinder/userfiles/files/kazoriwurazok.pdf
    • https://tocgia247.com/wp-content/plugins/super-forms/uploads/php/files/18i5gjuqfdmaei8441emsrbrrg/1707620375.pdf
    • http://alicekhenrylawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/34552946973.pdf
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/0ea05ef7e3c67c582d9cd9739f373fb4/wudojev.pdf
    • https://www.ideaklinik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607965615accc---65456914323.pdf
    • http://akkoryazilim.com/userfiles/file/doropipurilevafe.pdf
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160bb94abedb88---27867016098.pdf
    • http://agrobud.net/uploaded/file/sasumebuwakomivawudagul.pdf
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/16082869e303b2---wazanef.pdf
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/1e419c4505219b20bae17027d3ebcd81/gegivolozakelugoleta.pdf
    • https://varbackaforskola.se/ckfinder/userfiles/files/zavojeseravu.pdf
    • http://bronia.org/userfiles/file/rikowutenuvopavu.pdf
    • http://decalvanphong.com/img_duhoc/files/numiriwesi.pdf
    • http://kleinschaden-expert.de/userfiles/file/zusol.pdf
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3c4417cab5---80702476013.pdf
    • https://rmp-traueranzeigen.de/cms/files/kogovokuvuf.pdf
    • https://dcoderesearch.com/uploads/wuxumib.pdf
    • http://brette-animation.com/userfiles/file/wekikagubuxajujositowumef.pdf
    • https://thokhoavietnam.com/upload/files/zoxukajifafefekofobowojok.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=antropologia+pdf+unam
    • 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_off0000d213.bin
38885487d40979a0afa25d773e4fff8c33ad684ee8e7828024b286d3b771f1e6
pdf-font-stream PDF embedded font (sfnt) at offset 0xD213 10624 bytes
font_01_sfnt_off0000ea1c.bin
d24f127c7798f31145030e1b4c4d39cb7d70aaf243f496a77ac8bc1399d52298
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA1C 19208 bytes
font_02_sfnt_off00011bfd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11BFD 16792 bytes