Malicious PDF — malware analysis report

Static analysis result for SHA-256 9dbdb51cccb0a402…

MALICIOUS

PDF

81.4 KB Created: 2021-09-08 01:13:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 73297368ceec6d770e51a1598b8851e1 SHA-1: 09daca5bff45ac5b87eac12ba31da2607227a8a4 SHA-256: 9dbdb51cccb0a4026e37981fd7a083da94e36ea8637dff746f543c65368c7ab6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate the document functions as a link farm, directing users to multiple external URLs, many of which are hosted on compromised CMS upload directories or disposable domains. While no scripts were explicitly extracted, the nature of PDF link farms often involves JavaScript to facilitate redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://anaksemut.com/contents/files/25089985983.pdf In PDF document text
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/3d3c57df396ee2c962055928677e9cfd/tazudurasako.pdfIn PDF document text
    • http://lalinpress.com/ckfinder/userfiles/files/87368780661.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/ptlehggi258c88qhpk1jeir4st/zezoruxupa.pdfIn PDF document text
    • https://szalkasszorutacskok.hu/app/webroot/files/content/files/dizafetulubapanobesoredig.pdfIn PDF document text
    • http://nfrostov.ru/upload/files/loxagoxajozor.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/qaocsr2nfqsabcauujupgelhcm/ripopuxalapiludawugab.pdfIn PDF document text
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/4899d24c42e680fff6705a14096c7aa6/48555278814.pdfIn PDF document text
    • https://palcev.ru/userfiles/file/rafodoleletuxosixud.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/33302664564.pdfIn PDF document text
    • https://isabellepieman.com/userfiles/file/36373135602.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/48192411915.pdfIn PDF document text
    • https://pubs-icfas.org/icfas_new/dev/ckfinder/userfiles/files/41031834130.pdfIn PDF document text
    • http://zhongguohuachun.com/d/files/kudoxovodugitidol.pdfIn PDF document text
    • https://www.bakirkoytemsilcisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082ef290b9e1---30111145050.pdfIn PDF document text
    • https://canevastoilestjean.com/upload/editor/file/lirifavanebekexamere.pdfIn PDF document text
    • http://intertexmedical.com/userfiles/files/7230808878.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160919349307ad---99342954660.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/1b44667337a7172502db333659e87ed0/7966432733.pdfIn PDF document text
    • http://ayhancevik.com/images_upload/files/pisirodezip.pdfIn PDF document text
    • http://ebslang.net/_UploadFile/Images/file/77760911620.pdfIn PDF document text
    • http://nct-vn.com/userfiles/file/zuxuwefimaradulut.pdfIn PDF document text
    • http://jan-fotografie.nl/upload/files/soluvigerawu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=maintien+de+la+paix+et+de+la+s%C3%A9curit%C3%A9+internationales+pdfPDF 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_off0000d31a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD31A 10960 bytes
SHA-256: a50b33c80223cfafa17cf6addba7a15e6ddaed4ada83e585c4fb438aa185caa7
font_01_sfnt_off0000ec59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC59 19380 bytes
SHA-256: d87488b104f267964453a3b6fca1ab445824e2b6131647b31768b14cb97c4c64
font_02_sfnt_off00011d35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D35 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1