Malicious PDF — malware analysis report

Static analysis result for SHA-256 889efd0164693e6a…

MALICIOUS

PDF

71.4 KB Created: 2021-09-26 03:28:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ae453d5027939a72725843c574a16284 SHA-1: 3d996a73b5308cef727d2d3327c4487c56101625 SHA-256: 889efd0164693e6a8167d7a3062244841dd65a2c42611b593f5619339b89fe7b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The presence of numerous unknown and potentially malicious URLs suggests an attempt to distribute further malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://ekransamara.ru/files/3629674547.pdf In PDF document text
    • http://concilianavarra.com/userfiles/files/77441749133.pdfIn PDF document text
    • http://jsushibrea.com/uploads/files/somijof.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/16139f17f47043---9661161120.pdfIn PDF document text
    • http://jjinline.org/file_upload/file/90047473972.pdfIn PDF document text
    • https://cbdc.co/uploads/ckfinder/userfiles/files/zeximuluruvozegenerovukaf.pdfIn PDF document text
    • http://studiobaliva.eu/userfiles/files/18543717922.pdfIn PDF document text
    • http://sdds.be/userfiles/file/24167262180.pdfIn PDF document text
    • http://chizclean.ru/files/fck/file/1314068326.pdfIn PDF document text
    • http://www.dilipprabhavalkar.com/images/file/weletanefonelevolakuna.pdfIn PDF document text
    • http://xn--d1achljw0b.xn--p1ai/content/upload/65226478914.pdfIn PDF document text
    • http://strandedtattoo.net/file/15641080151.pdfIn PDF document text
    • http://www.gdchgs.com/admin/img/files/8243930662.pdfIn PDF document text
    • http://lngpetro.com/userfiles/file/mavupemixerabu.pdfIn PDF document text
    • http://ubytovna-krumlov.cz/userfiles/file/19022369386.pdfIn PDF document text
    • https://southwestlooms.com/admin/userfiles/files/netopu.pdfIn PDF document text
    • https://pkmoscow.ru/ckfinder/userfiles/files/bibikojowup.pdfIn PDF document text
    • https://divanich96.ru/admin/ckfinder/userfiles/files/nijesad.pdfIn PDF document text
    • http://songhakbbq.com/uploads/files/60635865933.pdfIn PDF document text
    • https://www.kuwaitpolyurethane.com/ckfinder/userfiles/files/nuzipatefajasafowutixafo.pdfIn PDF document text
    • https://at1apigroup3.com/contents/files/29952981744.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/b8e6fp4c3ngbq2a30h23gc6pse/57344449903.pdfIn PDF document text
    • http://progetec.org/userfiles/files/44421164503.pdfIn PDF document text
    • http://goldstecq.com/userfiles/file/dizazufosa.pdfIn PDF document text
    • http://topstec.com/d/files/xunegujisakevukuwuf.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614409aecafd4---doligokuma.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=bharat+full+movie+salman+khan+onlinePDF 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_off0000b300.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB300 10792 bytes
SHA-256: f132b58b826d614149ccc2de4c8df821876c7f115f4cf7dd531585b2c72ba9c0
font_01_sfnt_off0000cbbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBBD 17388 bytes
SHA-256: 61136211b79b9ec89da973294efe51368723ea6d6b1565507200b974a186e645
font_02_sfnt_off0000f7dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1