Malicious PDF — malware analysis report

Static analysis result for SHA-256 51592dd5a9c89a66…

MALICIOUS

PDF

79.9 KB Created: 2021-09-18 17:32:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2c13ef915e2789de29e01a9c86cd78f2 SHA-1: d48009d9bf923aca7e17745deabd1042ee1317fe SHA-256: 51592dd5a9c89a66b272a2081bf7026a2135c3ea5a0634d00e4b881afc6bc50b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many of which point to disposable hosting or compromised CMS uploads, forming a link farm. The presence of a URL with a 'utm_term' parameter suggests a phishing or SEO manipulation attempt. ClamAV detection and ML classification strongly indicate malicious intent, likely phishing.

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://synerhu.ru/uplcv?utm_term=otg+usb+not+working+on+phone PDF link annotation
    • https://journeywithmypet.com/ckfinder/userfiles/files/7200021622.pdfIn PDF document text
    • http://naturestuff.nl/siteimages/file/zujidiro.pdfIn PDF document text
    • http://jtravel.clickis.kr/FileData/ckfinder/files/20210902_DBDB9C2A4D6B7CAC.pdfIn PDF document text
    • https://confidence-ist.mktechsol.com/ckfinder/userfiles/files/39902624343.pdfIn PDF document text
    • http://aadcnfgl.netsociality.com/upload/files/80367778552.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/gijepexalemub.pdfIn PDF document text
    • http://ecohouse-lab.com/userfiles/file/lumevetarewefiwepudatixu.pdfIn PDF document text
    • http://thomasgearon.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/69500064278.pdfIn PDF document text
    • http://saothienemb.com/uploads/images/files/82920564750.pdfIn PDF document text
    • https://opsclown.it/ckfinder/userfiles/files/puvupilakufokapajutes.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1612eb159d9f4e---ferefoxuku.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e00c8eddef---werilefunomovu.pdfIn PDF document text
    • https://alshaabcoop.com/userfiles/file/27525183392.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/f0d138abb3f11b6017303fcd07f95d18/90122753351.pdfIn PDF document text
    • https://igescanada.com/ckfinder/userfiles/files/jenis.pdfIn PDF document text
    • http://oldadmin.k12cart.com/media/files/gugupebavagelefafubowilit.pdfIn PDF document text
    • https://digireg.nu/upload/88930438863.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/161322736e7b53---75138395140.pdfIn PDF document text
    • http://svatba-emi.com/uploads/pages/files/darejodigiw.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/8680591042.pdfIn PDF document text
    • http://djpress.pl/Image/files/tuxetikelujikomoluxe.pdfIn PDF document text
    • https://alhurwallpaper.com/Files/files/52274959776.pdfIn PDF document text
    • https://matratva.in/userfiles/file/77310462874.pdfIn PDF document text
    • http://drapa-technika.cz/UserFiles/File/duvapumesinumavitoxe.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_off0000d134.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD134 10764 bytes
SHA-256: 26f84e8bc137ce0b8a686c8ecdd0014e1239aaf8d35d4185ef4be4602d9d7d82
font_01_sfnt_off0000e9cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9CF 18716 bytes
SHA-256: 2bc0c25ba984173a41447093d5ca133b5a39343e62e760b31d997e3c9503653a
font_02_sfnt_off00011a55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A55 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1