Malicious PDF — malware analysis report

Static analysis result for SHA-256 23022628c5aa2fe7…

MALICIOUS

PDF

114.1 KB Created: 2021-09-14 14:12:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: ee55e76ca1893d39fb3eb72c66d6524c SHA-1: 8e1810842d31ee1012f2c6d69e3459a4e94f2f3f SHA-256: 23022628c5aa2fe730f18c596e092c8eeefb857029ee37b731ff0c44426fb642
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the extensive use of external links is the primary attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9930

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=space+gangster+2+hack+download PDF link annotation
    • http://adhdesign.de/userContent/files/20210906135351-71155302501.pdfIn PDF document text
    • http://betheaskssd.com/flash/betheaskssd.com/file/xunezevuwatajakamejomira.pdfIn PDF document text
    • http://www.photonics-science.com/ckfinder/userfiles/files/83203985954.pdfIn PDF document text
    • https://sunkamalzemecilik.com/userfiles/file/nexukunatuxevajogaxo.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132cca20292b---44738863943.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/443sp1b6hod13u0eq94aaofhl5/nedujij.pdfIn PDF document text
    • http://chaukitchen.com/uploads/files/96358132470.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/5c2896d4117bb582613de6ed72a3e4e8/fejume.pdfIn PDF document text
    • http://karpatskiles.ru/store/files/53169022758.pdfIn PDF document text
    • http://khachsansapa.vn/webroot/img/files/xapesajar.pdfIn PDF document text
    • https://stabiactiv.com/userfiles/file/fisura.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16132588213ea5---82773045025.pdfIn PDF document text
    • http://galantemontagnana.it/ckfinder/userfiles/files/4432392463.pdfIn PDF document text
    • http://kunmobile.vn/files/uploaded/20210901/file/56518626606.pdfIn PDF document text
    • http://herborgthailand.com/file_media/file_image/file/9091323008.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d53335c8d3---73267410038.pdfIn PDF document text
    • https://olgunbey.com/upload/ckfinder/files/71275285481.pdfIn PDF document text
    • http://the100voicesofgospel.de/fichiers/newsletter/file/57826770020.pdfIn PDF document text
    • http://kdwatch.net/upload/files/2021090714581667.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/2j8dtme44d7nptmkd138812hf7/pusag.pdfIn PDF document text
    • https://gosselindesign.com/images/from_fckeditor/fichiers/85214925800.pdfIn PDF document text
    • http://abwingsjanaf.com/uploads/files/tapafirojevajepugovomife.pdfIn PDF document text
    • http://challendor.com/fckeditor/upload/file/78215678142.pdfIn PDF document text
    • https://drrajanmahtani.com/userfiles/files/83287480176.pdfIn PDF document text
    • http://drairtools.com/ckfinder/userfiles/files/xidivotilojezadenarugit.pdfIn PDF document text
    • https://qfuse.it/images/uploaded_files/ckfinder/files/1631296190_b9566290bb.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_off000156bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156BD 18820 bytes
SHA-256: 0a3e594a2d4dee292b873ed46d4f34b94ec909b2b85e13838c839a042ad3a7ee
font_01_sfnt_off00018876.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18876 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001a08d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A08D 11072 bytes
SHA-256: fecdb602600b3680f8e8d0b805ea9a86e5f74118cf01b2f0c54e381df0a161df