Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c162e782d2f359b…

MALICIOUS

PDF

77.5 KB Created: 2021-09-16 05:31:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 17f3dc31df1e9e3f7683371d5944d0f7 SHA-1: f64240f66f64ad95dd63cf10d894b8832f1dc95d SHA-256: 5c162e782d2f359b30e395801ec4e24f8219d1fc8d6bd489c7c1666b2f7092b9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics as a link farm and a potential phishing or malware distribution vector. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is heavily obfuscated and unreadable, but the presence of numerous external URLs, many pointing to compromised CMS uploads or disposable hosting, suggests a phishing or credential harvesting attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://queure.ru/uplcv?utm_term=rich+fruit+cake+recipe+delia+smith PDF link annotation
    • http://vinag7furniture.com/app/webroot/files/editor_upload/files/23186186295.pdfIn PDF document text
    • http://antropolog.ru/userfiles/file/4148115262.pdfIn PDF document text
    • https://vsetinrally.cz/userfiles/file/danafim.pdfIn PDF document text
    • http://kamnitikamini.si/upload/files/vafiwirox.pdfIn PDF document text
    • https://aimhc.com/userfiles/file/gokimivivubosete.pdfIn PDF document text
    • http://zsdbiopharm.com/upload/files/gamatizewekeroto.pdfIn PDF document text
    • http://theponghop.com/upload/files/62483434470.pdfIn PDF document text
    • http://elitsatodorova.com/uploadfiles/file/77340820987.pdfIn PDF document text
    • http://yuanhebiotech.com/upload/files/xodeluziwupinoraxusejis.pdfIn PDF document text
    • http://autolubitel-irk.ru/userfiles/file/vekefafewitefegituku.pdfIn PDF document text
    • http://akwarella.pl/user_uploads/file/41627756682.pdfIn PDF document text
    • http://yunnanyingxiang.com/ckfinder/userfiles/files/38082669458.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613cbe0318359---93987471890.pdfIn PDF document text
    • http://sinostandards.net/upload/files/dadokinovegurudibaremu.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fcb25881ae---52528191714.pdfIn PDF document text
    • https://horkolas-gatlas.hu/ufiles/file/15596360805.pdfIn PDF document text
    • http://zygzak.eu/foto_dane/wysiwyg/File/50230300619.pdfIn PDF document text
    • https://goodmix-psc.com/userfiles/files/66043810516.pdfIn PDF document text
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/1059dab80b56aecbc2b12e3d515a9d4f/26830098668.pdfIn PDF document text
    • http://wabasnb.com/files/fckeditor/file/15555208176135fcd4a827d.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/16142909b3268e---kajimom.pdfIn PDF document text
    • http://bulgankhangai.mn/userfiles/files/21584889559.pdfIn PDF document text
    • http://www.polni.si/Images/files/sikinugobemowifovijor.pdfIn 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://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_off0000c8be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8BE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e0d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0D5 10900 bytes
SHA-256: 297042a6a4bdd07530d5a8e913c445e681b9b17e6b9b99a833457c5415b7ea67
font_02_sfnt_off0000fa0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA0B 17972 bytes
SHA-256: 1a48129673a06fd5f033e7498d9c513f78864f627897e8db6a447587ed53f014