Malicious PDF — malware analysis report

Static analysis result for SHA-256 87c0f312283c3f40…

MALICIOUS

PDF

71.2 KB Created: 2021-09-25 00:19:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4c4a5e251ecaddb75cea87f255fd0704 SHA-1: 2d1c12791e211d227c58f33d22398e5d5d594282 SHA-256: 87c0f312283c3f406c30a0f940689d0d0f8fc0cc18e72ceb70c5c6bff16141cd
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with multiple URLs pointing to potentially compromised WordPress upload directories. The embedded URLs suggest an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143eab0a0188---foxuxulupiwopoziragezi.pdf
    • https://berbagiangka.com/contents/files/repuxozidogelixop.pdf
    • http://thebrownbag.vn/upload/files/biwugaserelip.pdf
    • https://booburger.myagenda.cz/pictures/editor/files/95559613674.pdf
    • http://hockjoohin.com/admin/uploads/file/pigogaguji.pdf
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d37efbb35c---kiratunenaguginipivileni.pdf
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/16141f4408239f---buzibenixajezed.pdf
    • https://tennis-samara.ru/img/file/poririzove.pdf
    • https://mekongtransport.com/upload/userfiles/files/91496002511.pdf
    • http://master-sign.ru/ckfinder/userfiles/files/sorovibufuvimidej.pdf
    • http://sksound.com/userfiles/file/rezikub.pdf
    • http://warehousetraining.ie/images/tefuvipekujebilujowepaw.pdf
    • http://evaemlak.com/userfiles/file///kuxunovakewofumibupo.pdf
    • https://chmelo.hu/sites/default/files/file/dekelafitumedo.pdf
    • https://phu-komplex.pl/pliki/file/rosexalufogonojukasaj.pdf
    • http://ophirtonhotel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161464d4723b09---buvixukusowusexomip.pdf
    • http://cana.vn/uploads/userfiles/file/wudomitajalujowo.pdf
    • http://bezpiecznamlodosc.org/files/file/69434181448.pdf
    • https://bomando.bomsolar.com/uploadfiles/files/zemuxotidewis.pdf
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/49bfmkta5pqlii4pr4k8pc34o4/zozamoravazutofifola.pdf
    • http://reyazahmad.bscsaoner.in/ckfinder/userfiles/files/62005876450.pdf
    • https://gizaviation.com/uploads/files/21732614715.pdf
    • https://casartigianiudine.busletter.it/ckfinder/userfiles/files/70693325267.pdf
    • http://csc-0898.com/userfiles/file/20210924183714_ug0jlo.pdf
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/35db31fb73a55c8ed45fe368ac34eb64/31189458095.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=wonder+woman+1984+telugu+movie+online
    • 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_off0000b503.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB503 16792 bytes
font_01_sfnt_off0000cd1a.bin
706dd0e1be3442c764011d2558ed71eca0054809fab8675e0cd4171907e4c2a2
pdf-font-stream PDF embedded font (sfnt) at offset 0xCD1A 11172 bytes
font_02_sfnt_off0000e725.bin
40c6696ae144def38f86afd32354e9f5e9bc590211620478accc396989bbe7df
pdf-font-stream PDF embedded font (sfnt) at offset 0xE725 14992 bytes