Malicious PDF — malware analysis report

Static analysis result for SHA-256 9d91037766606d1a…

MALICIOUS

PDF

85.6 KB Created: 2021-07-31 16:21:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a357195c7cd8e70856373b50b0f1e548 SHA-1: ecfa6cddcf51f24c0caf065dd0bb985c62b68cf1 SHA-256: 9d91037766606d1a4163c10a58f8edd29a326a5a92fe57d4d5d9e76c3cc988d3
164 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of numerous links pointing to compromised CMS uploads and disposable hosting suggests a link farm designed to redirect users to malicious content. The heuristic 'SE_DOWNLOAD_BUTTON' further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://readandenjoy.ae/userfiles/files/sigununosa.pdf In PDF document text
    • http://joelcsimonesq.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/41383205479.pdfIn PDF document text
    • http://kotolantopeni.cz/file/84381137059.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160b5556e6ccb0---25653354209.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/t6nlogmasou7r0tm0p85dfpusk/55723326596.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609657fa544e1---84817916005.pdfIn PDF document text
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/6c5423b17e5921329474517ad51c2969/vunevatedawetetulukamugo.pdfIn PDF document text
    • https://etadelloro.it/images/file/gegigusulanetemar.pdfIn PDF document text
    • http://www.makattakasinti.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071e21546c53---40383832657.pdfIn PDF document text
    • https://bataretak.com/img/files/file/vunefaxakimuwipefi.pdfIn PDF document text
    • http://hublihorse.com/uploads/userfiles/files/30875589112.pdfIn PDF document text
    • https://xosobacninh.vn/webroot/img/files/mefivezas.pdfIn PDF document text
    • http://dyglas.com/userData/board/file/xitumod.pdfIn PDF document text
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/ae24i0nl992j13pl79gi2bl46k/78240848184.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/160ade4099ced0---99194207967.pdfIn PDF document text
    • https://santechnikosdarbai.lt/images/files/potumopitizenefuzo.pdfIn PDF document text
    • http://studiomalpocher.it/userfiles/files/gorimedopirowosokafo.pdfIn PDF document text
    • https://cartolmania.it/file/83410219364.pdfIn PDF document text
    • https://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/9e3d2d5e374c0024dc8445d11c1b29c7/rabodoraf.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16070db1186e9f---fidigenasidexagakepiw.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095b128cf723---46087721990.pdfIn PDF document text
    • http://dok-vo.ru/userfiles/file/75054086278.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=adfly+auto+clicker+apkPDF 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_off0000e833.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE833 10628 bytes
SHA-256: 9bdb49fed62fbe721f178db7417975417c72e5027383af271afd9f08dda57653
font_01_sfnt_off000100b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000118c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118C6 17556 bytes
SHA-256: d8b534b19ef8ac31bd30a181e7e91ad018f335318631efaea52ee03c0de8a45d