Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a643a5cc7afad90…

MALICIOUS

PDF

78.3 KB Created: 2021-06-11 22:06:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f01382fd1a947e17395a136353239d93 SHA-1: d2f4387abd6975224f8466a2ca9f51ff1523c7d3 SHA-256: 9a643a5cc7afad90c81e0a2906801e91035f398398d555c64a2a9b52a2e29b05
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 websites or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The document body is heavily obfuscated and contains metadata related to wkhtmltopdf, but the primary malicious functionality appears to be the extensive use of external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://chcial.ru/uplcv?utm_term=preset+guitar+rig+5+avenged+sevenfold
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/0c1edc80a91f0fe6e312b4feaaeeadf9/dajufubabefavi.pdf
    • http://isgsrl.it/images/file/23165864407.pdf
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16078ec108b92b---66880280072.pdf
    • http://nedirajtebosnu.net/userfiles/file/bilukozilamasunufi.pdf
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607bae19bf869---lopakumi.pdf
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609be70669225---kapunoxolefegib.pdf
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/vrgct9qqadfutf3gqlltva6ami/55005454457.pdf
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081156315fe9---10636760911.pdf
    • https://aedwea.com/upload/foto/nonexokoki.pdf
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f5c2264998---kesunafapujus.pdf
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608367f26e1ff---62536723070.pdf
    • http://clarkstownhs64.com/clients/2/25/255c49a504cbad61718694d8b78dfcdd/File/65015919721.pdf
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16083e8ce5cb2d---28731422479.pdf
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae327c6dab2---89536409569.pdf
    • http://askort.pl/Upload/file/xevukekupuza.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f5da.bin
afb9a424d8d038b79ec142c0865305fbfd9db7a0db4c045c25d05e1df1edea2c		 pdf-font-stream PDF embedded font (sfnt) at offset 0xF5DA 5260 bytes
font_01_sfnt_off000107d9.bin
1fc8e32d3bb95230c805676566c60fcc8cb59baa5351fe997730b1968b5758ae		 pdf-font-stream PDF embedded font (sfnt) at offset 0x107D9 10860 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.