Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8b48d74ecb2be01…

MALICIOUS

PDF

94.3 KB Created: 2021-07-04 13:10:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: ab8f96884854fb0b31e5dba278f0e9b6 SHA-1: 2983083d32a7000e64d57b470103fea6e3c94df0 SHA-256: d8b48d74ecb2be01aa472af8c06659063863557205b572c56df89661c6b5b879
156 Risk Score

Malware Insights

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

The sample is a PDF file detected by ClamAV as Pdf.Phishing.Trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised WordPress upload storage locations. The ML classifier also strongly flagged this PDF as malicious. The primary attack pattern involves directing users to potentially malicious external URLs hosted on compromised websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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 https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/bd8fr6eevjo5mgi8qf056gohch/ditakefa.pdf In PDF document text
    • http://koryosushi.com/uploads/files/64544718073.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/06edb5a7d00b88ba4d1a941d43debad8/10194594905.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089b99b4e835---dolasi.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e1265290cef---kosananonawenifafopu.pdfIn PDF document text
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b1b3a13ccc1---zanexibanigopefek.pdfIn PDF document text
    • http://mistral-paints.cz/userfiles/files/silenuxi.pdfIn PDF document text
    • https://cmoretv.com/userfiles/nerudaduvebogedixowumamav.pdfIn PDF document text
    • https://hbphoto.ca/resimler/files/nofugizegeruralanitibupi.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160ae749f5214d---sibojurugunetazudibaleja.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bd1041315b2---36700870116.pdfIn PDF document text
    • https://studiovizia.com/webroot/img/content/files/xajosewugofegivorimifav.pdfIn PDF document text
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/6ovbcn4303i6hlaahc3jdq7l5e/20932492097.pdfIn PDF document text
    • https://jetzterstrecht.hamburg/wp-content/plugins/super-forms/uploads/php/files/14foalknuafe424afbhuipjalf/purokunafimasavoko.pdfIn PDF document text
    • http://acpiindia.com/userfiles/file/62791239047.pdfIn PDF document text
    • https://dcoderesearch.com/uploads/fuzuvakare.pdfIn PDF document text
    • http://primebrokeragetx.com/ckfinder/userfiles/files/82669874375.pdfIn PDF document text
    • http://maremio.ru/admin/ckfinder/userfiles/files/83800931865.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094cd5d42bfb---poxeruw.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/4kkgl7ktvgt4ljat76dco1p2k6/23153499750.pdfIn PDF document text
    • http://ats-dz.com/userfiles/file/97810850820.pdfIn PDF document text
    • http://timebank.ru/sites/default/files/photos/pagefile/71584884639.pdfIn PDF document text
    • https://leo-translate.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16077dc2e1333a---81244311684.pdfIn PDF document text
    • http://lnshiyue.com/userfiles/file/20210527212245_1734373280.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/45c2d3b80b2d62ba96ba5d09b03644be/rosudarab.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=dtv+questions+and+answersPDF 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_off00010e59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E59 17180 bytes
SHA-256: 74dc9428ad7602fff8bb497d56c8f9d5d43c97e4b7f493a41e50f9ca3499ba36
font_01_sfnt_off00013b8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B8A 10596 bytes
SHA-256: 40028e12e129f3c64256396fd68149547061071bd59e7d591b4eb68baf424070
font_02_sfnt_off000153c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x153C0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1