Malicious PDF — malware analysis report

Static analysis result for SHA-256 321bd4dd28a13d13…

MALICIOUS

PDF

86.0 KB Created: 2021-08-21 16:21:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: a08e2eac48ecab06ef17f9720b594c05 SHA-1: 1a315c56f78099af84759c5afd0a98cba4efcecc SHA-256: 321bd4dd28a13d13e9ce7ddc8f82d4dea0f9cd0d56f1ad15e310ce3bd389a649
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites hosting other PDFs, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure and URLs point to a multi-stage attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9919

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://ukrainski-rosyjski.pl/userfiles/file/72264412079.pdf In PDF document text
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/1607e4a2348692---59410187792.pdfIn PDF document text
    • http://apartamentosalbatros.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088cab71a3ec---wajovixasupukezagoko.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/f60f6ca4a8f06a324a429d82ae6e104b/zebidujojotasedepapa.pdfIn PDF document text
    • https://vidolamerica.org/wp-content/plugins/super-forms/uploads/php/files/b18953786c195b74fed8168b45ba32a0/zopamotiwawetadowodepimad.pdfIn PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/eivk2phhumv0i9ij5honri8c10/diwusedarejuxefibit.pdfIn PDF document text
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/ed96efb7824d6fc857234cc547b5fd79/66922426822.pdfIn PDF document text
    • https://tavcam.com/upload/ckfinder/files/folelupizukisos.pdfIn PDF document text
    • http://fijiembajak.com/uploads/ck_uploads/files/71239595479.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/e75af57caf4735aede1a70e734aba328/raripabapag.pdfIn PDF document text
    • https://forex-robo.org/wp-content/plugins/super-forms/uploads/php/files/6575051ef7d08e4fbea05d7a17b74ce8/83172108256.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611e94153e81c---gapezakaxoruvewumenibora.pdfIn PDF document text
    • http://belloverde.net/emailer/file/23600208010.pdfIn PDF document text
    • http://moscowprice.com/content/xuploadimages/file/wenesoz.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/160719d65083f2---kenofuramipifupi.pdfIn PDF document text
    • http://clarksville.net/wysiwygfiles/file/41285655000.pdfIn PDF document text
    • https://www.hosotte.com/ckfinder/userfiles/files/kaxumososed.pdfIn PDF document text
    • http://mtecommerce.it/public/news/file/25743048828.pdfIn PDF document text
    • http://xn--80adpfaaeictf0c6c7i.xn--p1ai/public/file/jutoluvenowugejibem.pdfIn PDF document text
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf04bd5a1cb---34625836890.pdfIn PDF document text
    • http://21cedu.com/pds/userfiles/files/70161474179.pdfIn PDF document text
    • http://ptaki.info/imgekoprojekty/files/labademisovuwegudolexo.pdfIn PDF document text
    • https://nilsagame.com/calisma2/files/uploads/61748101794.pdfIn PDF document text
    • https://coonvalleycc.com/userfiles/file/zovunenuvodojuva.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/eddea0c2084f4f8e6505cb4d7213272a/58379498906.pdfIn PDF document text
    • http://natproperty.com/userfiles/files/gifapugepujidewoxat.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=excel+sheet+for+crane+girder+design+of+continuousPDF 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_off0000ebc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBC2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000103d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103D9 10940 bytes
SHA-256: 90219bc4284a22326491895f76d9b3adcbb59fcc3821f1f6de58250cb1656ce0
font_02_sfnt_off00011cf7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CF7 17004 bytes
SHA-256: 29540c51169b90312e679ee5a52eec2665a3ee0214b7a6398a8405a097378dfc