Malicious PDF — malware analysis report

Static analysis result for SHA-256 491b356a74bb1c5c…

MALICIOUS

PDF

76.3 KB Created: 2021-06-13 11:05:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 16c27044a5ad5d5cba542a180b80e563 SHA-1: 3a3f21fcbfee1f9a3747b6efb2dc5d58594e168b SHA-256: 491b356a74bb1c5c422ced737977de5b9383c1e2a5c63c55052adb99cb3705b4
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. It functions as a link farm, directing users to multiple compromised WordPress sites and disposable hosting domains. The embedded URLs suggest an attempt to distribute phishing content or further malware payloads.

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://krisoc.ru/uplcv?utm_term=how+often+can+dogs+go+into+heat PDF link annotation
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b0d8bf325e---lemopifatij.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/318648edd1393fa77d1badbe65010305/62750010716.pdfIn PDF document text
    • http://creativeindustries.ru/uploads/userfiles/file/vefelapula.pdfIn PDF document text
    • https://hfdjet.com/wp-content/plugins/super-forms/uploads/php/files/043386ad0cab3027d37e6ddc017f37f2/83032724949.pdfIn PDF document text
    • http://aps-mes.com/files/file/vatoxegedodosatelizano.pdfIn PDF document text
    • https://aterhesseg.com/up_image/file/65166396173.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/a86a9b33ec38a4e5f16c80ccbb1efa84/49656896550.pdfIn PDF document text
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/u3ujb31g0cc6hs76r51em1s503/mujiluba.pdfIn PDF document text
    • http://jatyn.cn/upfiles/202105/file/1621542673.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/16097dff4c3a97---5759768731.pdfIn PDF document text
    • http://bhs-class1957.com/clients/35434/File/64349701315.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/a27f1307fb4c873fe5f851c7a929f158/vesur.pdfIn PDF document text
    • https://invest.pl/userfiles/file/duzarunogumavefugogage.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/55vo8m4u1au4ilebkhdecjnnd7/3976061257.pdfIn PDF document text
    • https://bhsbeacon.com/FCKeditor/file/bawezirilutiwajozemex.pdfIn PDF document text
    • https://bechtoldpaving.com/wp-content/plugins/super-forms/uploads/php/files/0832ac284f4cb30e25a0ba15a2af2555/lupox.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED80 5208 bytes
SHA-256: 48758224ead7a4be54fe162edf59925010605680c5c14f9a0372158eee7c03dc
font_01_sfnt_off0000ff57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF57 10776 bytes
SHA-256: e12ca80b79d197acbe40c0a6b7620998d88deb6cb01e748b131534cf82abe40e