Malicious PDF — malware analysis report

Static analysis result for SHA-256 878837e8c20c3913…

MALICIOUS

PDF

83.2 KB Created: 2021-08-30 03:23:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 36ea0c10c4796f357d77ee768b233a51 SHA-1: dec5a37e923bc8ad5a577c0825a6ac64fc7a2c6a SHA-256: 878837e8c20c3913fbc211f8136a996788346442e97b3509918e11f4e97488f9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs pointing to compromised WordPress sites, a common tactic for distributing malware or phishing content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure suggests a lure document designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608ad4ae7a81e---58530963931.pdf In PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/f257dd6fa67f013a89742b27620a0070/75443400477.pdfIn PDF document text
    • http://kronikarp.pl/ckfinder/userfiles/files/zafetekisarigikejav.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc01eeefbd---18429834193.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070f97ce76b6---fepil.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/4f62244c66f4a087c38213fa1fb79829/61439911478.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/db6735436a278490435ad6ce7b12eefe/67886199144.pdfIn PDF document text
    • http://www.evisiontiendaonline.com/ckfinder/userfiles/files/nawusikabaruxelomafoxuv.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbb84d1c9a8---verexavokesojanuvipun.pdfIn PDF document text
    • http://www.buildingmalawi.com/images/uploaded/documents/74421354976.pdfIn PDF document text
    • http://dzbnf.com/upload/file///84628793711.pdfIn PDF document text
    • http://stin-verdon.fr/assets/Image//files/bitagiwofoludikalopen.pdfIn PDF document text
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/c87f8d5410c16c58832dad0af037df4a/pizupuxuzitavo.pdfIn PDF document text
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/64db2e7502853fdf8c75b7f8967d6010/netupuvam.pdfIn PDF document text
    • http://gramercygrand.ru/files/file/36474551129.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb407c5283---97246128929.pdfIn PDF document text
    • http://smartarts.bg/userfiles/file/jozipofujeguvowevilul.pdfIn PDF document text
    • https://www.colline-eternelle.com/ckfinder/userfiles/files/moxavaxo.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/12bfd17937f209526c229aa5f26d3b25/lizileg.pdfIn PDF document text
    • http://studiotecnicopetrillo.eu/userfiles/files/65555326267.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/43cc9fe0ca594ca1a9eccacbdc410a6c/99992464795.pdfIn PDF document text
    • http://edilgroupdigiovanni.it/userfiles/files/16286593962.pdfIn PDF document text
    • http://satisfytech.com/ck/upload/files/puzolasamoxamoturiwi.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ddc21a2ef5---29611007619.pdfIn PDF document text
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/a6b29fda00db99a01096a40b53545861/14832562044.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=bloated+stomach+and+bleeding+between+periodsPDF 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_off0000de92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE92 11240 bytes
SHA-256: c5b2d9f2fcf36744bf9193251e9c8f7913e459353652b9fff3102689327f0825
font_01_sfnt_off0000f85a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF85A 16864 bytes
SHA-256: 099183a09bd9ad8c29e074a946d46500a4fbadf15795893afb3d24c4eeb236a2
font_02_sfnt_off0001243c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1243C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1