Malicious PDF — malware analysis report

Static analysis result for SHA-256 50135bd89f84f756…

MALICIOUS

PDF

71.5 KB Created: 2021-09-30 11:16:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: eefc1f85f3b25169b0915f3c73a10148 SHA-1: aec12546011513b13f6a641c5aab6c6b9636dc0c SHA-256: 50135bd89f84f756b49fb490eb93d74795dae63aa89d40961e4cef506ec23efc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, embedding numerous URLs that lead to compromised CMS uploads and disposable hosting. These links are likely used to redirect users to phishing sites or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://oniceh.ru/uplcv?utm_term=st+joseph+family+physicians+north+medical+center PDF link annotation
    • http://sunriverps.com/data/editor/file/37337414592.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fe8ee72230---goxevezezoxabuxakirab.pdfIn PDF document text
    • http://elitaliaweb.it/upload/file/paxowi.pdfIn PDF document text
    • http://maility.pl/_ADRESuserfiles/file/vudinedoladag.pdfIn PDF document text
    • https://ilo.tasksplan.com/userfiles/files/somorodisuludizelobagetik.pdfIn PDF document text
    • https://academiapreprod.riportico.com/userfiles/files/sutemagokumakebasowedup.pdfIn PDF document text
    • http://ippinnudon.com/uploads/files/setevabaxazukasavibuset.pdfIn PDF document text
    • http://tdjl.com/uploadfile/file///2021092914112285.pdfIn PDF document text
    • http://gzmzwl.com/Uploadfiles/files/fidususuvefivusegarume.pdfIn PDF document text
    • http://snabsz.ru/ckfinder/userfiles/files/738581164.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ed8185b896---digegobagevilowedidelog.pdfIn PDF document text
    • https://jmtours.co/aym_image/files/55662987235.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/161556db56d448---nizugifu.pdfIn PDF document text
    • http://dawahcity.com/userfiles/file/34560248534.pdfIn PDF document text
    • http://bowenlawmt.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/80849059720.pdfIn PDF document text
    • http://gitimohammadilakhimpur.org/ckfinder/userfiles/files/zoxijinilopetifizakogo.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/93481682312.pdfIn PDF document text
    • https://vinadesigndanang.vn/uploads/image/files/wowefuwilubigoruvupaw.pdfIn PDF document text
    • https://eatorhours.org/e-bussiness/fckimages/file/93307004832.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/aaf693d8871a45de36f39126747c3f81/noguzelapajamet.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614033d14f89d---35237781511.pdfIn PDF document text
    • https://agrilaui.com/userfiles/file/tulagukewukosevapo.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/5p04fgf722oi2hr1fdtnh2dr44/xudekoxawa.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_off0000b20e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB20E 16712 bytes
SHA-256: c8fc6421271d2c28bd4ae70f53fabee9955e4d44dbaea173025a56475f78e282
font_01_sfnt_off0000dc6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC6A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f481.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF481 11204 bytes
SHA-256: 0f0edfc472ca3cfadf5afe5cf6ffe199e6ffaa13ce0e8cb580c1ca51f294fce0