Malicious PDF — malware analysis report

Static analysis result for SHA-256 21fdc76071da745e…

MALICIOUS

PDF

83.5 KB Created: 2021-09-02 07:45:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: da05b485f21b8980bf2bd5970bc67bec SHA-1: 45c0b776ecbb93cda7dfe4547bc9ce34551bd747 SHA-256: 21fdc76071da745e45094b7cb3dc14b3f5aaaebe31b989f173f5b62a1485f17f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous external URIs and is identified as a link farm, suggesting it's designed to redirect users to potentially malicious websites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are consistent with a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

Heuristics 6

  • 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.
  • 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=concepts+of+marketing+management+pdf PDF link annotation
    • http://getampedmag.com/ckfinder/userfiles/files/wavorixexuvitakafoxerab.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc3f413dc7a---99672885276.pdfIn PDF document text
    • https://manajrgvaaradhi.com/cms-uploads/files/tijejuda.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/160e03806b92c6---desuxigavogeb.pdfIn PDF document text
    • http://sacoorhealth.pt/site/upload/file/79804373151.pdfIn PDF document text
    • http://tsradviseurs.nl/mailing/images/photo/file/83374962554.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082cd43c401b---wizubazaxilazuwavejewa.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/wubokezazujopekubijef.pdfIn PDF document text
    • http://www.benyowsky.com/resources/files/86401332741.pdfIn PDF document text
    • http://cabin4kids.org/clients/0/05/050cd0fff5f75fdfd14851583cc0de74/File/44423902886.pdfIn PDF document text
    • https://teenvolunteerhouston.org/wp-content/plugins/super-forms/uploads/php/files/3127a3cc56cb250dadcc456d21dc0b70/gaxabos.pdfIn PDF document text
    • http://newkontakt.ru/userfiles/images/file/97445626986.pdfIn PDF document text
    • https://k2salight.com/wp-content/plugins/super-forms/uploads/php/files/0b2264d6615750c82e9658783f6c60a8/xivedekimogumojuginodeli.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607a02e445318---zizususamofepivunotu.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ca6481d643d---xedofekase.pdfIn PDF document text
    • https://ozanetiket.com/TasarimAcarnet/serhali/upload/files/bubiw.pdfIn PDF document text
    • https://zerling.eu/nico/images/files/zowusamefaled.pdfIn PDF document text
    • http://bhavalaya.org/ckfinder/userfiles/files/10702001095.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adc566423be---jufavatipujadazini.pdfIn PDF document text
    • http://altelaw.com/uploads/image/file/nobebopigimevokige.pdfIn PDF document text
    • http://ltmetal.com/userfiles/files/doduwijakumapopig.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/51sh2ebethttf12bi89sifc8v1/76881979332.pdfIn PDF document text
    • http://peaceinsrilanka.lk/userfiles/file/gipamaw.pdfIn PDF document text
    • https://www.adilaltinsoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a356251fc7---fiweganemitiliteg.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_off0000e2d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2D9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000faf0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAF0 11040 bytes
SHA-256: 4a408953c5492a1eaf19a3bf69038f338e651b753935b57ee2143189a8857c29
font_02_sfnt_off00011474.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11474 16712 bytes
SHA-256: 8699581be17aff8a9091f79bc666c45178372502950f01c4783e9c7a59982884