Malicious PDF — malware analysis report

Static analysis result for SHA-256 af0b9d558e5502ae…

MALICIOUS

PDF

74.5 KB Created: 2021-09-26 09:59:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: cd238bf86e0ab4eec8218ba3b5917ea9 SHA-1: a2c29c6e12cd30dc48917d703a5d8789360c85ec SHA-256: af0b9d558e5502ae91304e13705a48dd2f1f4f84046d8fe4a294603133b82476
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous domains, several of which are identified as potentially compromised CMS uploads or hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://gabinetortodontyczny.eu/userfiles/file/44129942873.pdf In PDF document text
    • http://speakingaboutnetworking.com/ckfinder/userfiles/files/potazifa.pdfIn PDF document text
    • http://www.binghan.my/userfiles/file/75507063479.pdfIn PDF document text
    • https://safehouseservices.in/fckfiles/file/88236478965.pdfIn PDF document text
    • https://dla-pracownika.pl/pliki_user/File/zudutukisaroneta.pdfIn PDF document text
    • https://svenjakretschmer.com/ckfinder/userfiles/files/23469181141.pdfIn PDF document text
    • http://wintec-samu.hu/uploads/files/xudavafajelesom.pdfIn PDF document text
    • http://konakelektrik.com/userfiles/file/34592799033.pdfIn PDF document text
    • http://dalaichau.com/files/46629319347.pdfIn PDF document text
    • https://hram-uspeniya.ru/ckfinder/userfiles/files/47609694016.pdfIn PDF document text
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1614eec0e91f5a---dexiwukelamazavorujegi.pdfIn PDF document text
    • http://www.cavice.fi/tiedostot/files/bibalulufixumidunek.pdfIn PDF document text
    • https://yuktogel.com/contents/files/danosafobawugizivigugesis.pdfIn PDF document text
    • http://www.ppk-kp3k.kkp.go.id/ver2/extra/ckfinder/core/connector/php/media/ckfinder/files/89517526726.pdfIn PDF document text
    • http://www.520amis.com/upload/files/bimeka.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/1613f55c37e939---74995473633.pdfIn PDF document text
    • http://lighthouse-connection.at/myPix/file/gunof.pdfIn PDF document text
    • https://ihotel2b.com/upfiles/editor/files/56766844944.pdfIn PDF document text
    • http://blessingsngo.in/userfiles/files/basojikisuripasunigajo.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/tl31m7ocro00ivquf03orosbi5/86978046048.pdfIn PDF document text
    • https://serihosting.com/calisma2/files/uploads/rolunogofogejufugavix.pdfIn PDF document text
    • http://tatugigo.com/ckfinder/userfiles/files/6592906327.pdfIn PDF document text
    • https://seikai.jp/free_images/files/75626501648.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16144d5de6cccc---13021069054.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=custom+android+app+development+companyPDF 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_off0000b99a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB99A 18988 bytes
SHA-256: 34309f2ec71bc7d84287850a6e41371093e6a27fcc4f55e0dc6e8e7fc614f408
font_01_sfnt_off0000ea6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA6E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010285.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10285 10984 bytes
SHA-256: 7f4fb75c39d623c68a12d8b8e404bedebd77f821f66cf7510878b432a11cee84