Malicious PDF — malware analysis report

Static analysis result for SHA-256 f41718b3495cb51b…

MALICIOUS

PDF

169.8 KB Created: 2021-06-19 23:23:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: d23524873807b7875036940f0bdab273 SHA-1: ae40394883a135d5735b2d7c8967354ec2c93b22 SHA-256: f41718b3495cb51b195d540c3bfbe49b4ef224aa3d6471765d14b10baf869863
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics as a link farm, with many URLs pointing to compromised CMS uploads and disposable hosting. The ML classifier and ClamAV also identified it as malicious, specifically a phishing trojan. The document body, though heavily obfuscated, contains references to URLs that are likely intended to redirect the user to malicious sites, facilitating further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ae5c922458d---33243149753.pdf In PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/111438d060e3e3363c5fea7e479b6e5f/losanafuwufilisevosu.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4b35d6e348---zivexaf.pdfIn PDF document text
    • https://acrgroup.nl/userfiles/file/96552858142.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16087328baa027---jexirerokunoxawokedabeza.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc20fb9347---60097308442.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16079c108e5574---30705189745.pdfIn PDF document text
    • http://zonazero.es/userfiles/file/11525678626.pdfIn PDF document text
    • http://krzysztofmalec.pl/gfx/fck/file/vividavujopazo.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160bc03d9923d1---18426143136.pdfIn PDF document text
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607db89352efe---ditot.pdfIn PDF document text
    • http://hydrem.ru/images/file/2988647892.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16076b33cbf275---53289793677.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/14863226443.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=soccer+skin+with+candy+axePDF 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://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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00023f71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x23F71 2952 bytes
SHA-256: e211f2d6e0d1bf1fd17bd5150bc2724fb7c0f1d37b1c69b855d9dcad8de34ab0
font_01_sfnt_off000249ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x249FF 5424 bytes
SHA-256: 4b61d76fa24fc86c6aa421bce1728f83500d97f1e8249601ab05356a8a166dfa
font_02_sfnt_off00025c87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x25C87 11688 bytes
SHA-256: 2b51a327605cd211f83517d35b2653bd07ac0a0609337cdff93dc1b48bcc48f5
font_03_sfnt_off00028455.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x28455 16120 bytes
SHA-256: cf1f5adb226054e61b48b869043dcbfeac2ed8a78db67378db5d542e5772dc50