Malicious PDF — malware analysis report

Static analysis result for SHA-256 43c383be9ac3b44f…

MALICIOUS

PDF

75.6 KB Created: 2021-06-22 15:35:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: e7bbf236cbf0a5b92282ec989392879e SHA-1: 4e54c827c28def2e01cab5e3126f92ad55729639 SHA-256: 43c383be9ac3b44f1d819ef90e209868805a0719274ecd3923d3b3e22e6be5b9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS uploads. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, and the presence of external URIs points towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://catamma.ru/uplcv?utm_term=how+many+pound+is+45+kg PDF link annotation
    • http://physiotherapy-warwickshire.com/user_file/file/72050171148.pdfIn PDF document text
    • https://www.jscorporation.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607f5aaf18e4b---kanaxav.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088d70b16ab7---gezaxutanirimasamaru.pdfIn PDF document text
    • http://chanakyaaerospacedefence.com/userfiles/file/wupifuwitedibefawitewama.pdfIn PDF document text
    • https://acryl-bg.com/userfiles/file/lurunusipekeliguzuj.pdfIn PDF document text
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/r2k3btpuafusr25caadaghfral/82694870226.pdfIn PDF document text
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/trda7u7jpipijpsbav82bggo1i/dumenasasizevewi.pdfIn PDF document text
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/564f3ed93e7479656228e413fcbcc677/belobazudo.pdfIn PDF document text
    • https://argentinaproduct.com/ckfinder/userfiles/files/30671242594.pdfIn PDF document text
    • https://gbagencement.fr/uploads/file/20991647650.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac1ed98d4b5---guwafer.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/ti8t0ua13kip1jaqrtnlcrnup8/31037720592.pdfIn PDF document text
    • http://kayamedbursa.com/userfiles/file/vudov.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/6adhrs6a64m5rmm3bss776bp17/zefinixadanazilireber.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn 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_off0000d2e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2E6 5580 bytes
SHA-256: d4cd1521803538fa77c852873754d717a1cbf858e8fe4f024ccd33658791233a
font_01_sfnt_off0000e5fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5FC 10620 bytes
SHA-256: 25558698d19b5236d20430c326f9b8dd3b5d41f1bf65b9eb86b737b070cf36e8
font_02_sfnt_off00010aa6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AA6 16216 bytes
SHA-256: 0488c9f99e0fcd21ca2988e9d429c6d59fec344e78892dfd70b5e7a88f9c948a