Malicious PDF — malware analysis report

Static analysis result for SHA-256 c51b59d9535ad84a…

MALICIOUS

PDF

86.7 KB Created: 2021-07-21 04:15:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7f275a63f0d705c71010984a3c25b4ec SHA-1: d2ce9c4c79a5e1f38c3377207a327afbe8781db3 SHA-256: c51b59d9535ad84ae4da891b46421b9db298253b3160d067f136514036297c0d
156 Risk Score

Malware Insights

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

The ML classifier and ClamAV both flagged this PDF as malicious, with high confidence. Heuristics indicate the PDF contains a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting a phishing or malware distribution attempt. The document body was unreadable, but the presence of numerous external links and the overall structure strongly suggest a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://rheinmotel.com/userfiles/file/22991489260.pdf
    • http://tksvolga.ru/userfiles/file/85599536753.pdf
    • http://barcabianca.eu/upload/file/xedorelu.pdf
    • https://angkoronetour.com/userfiles/file/50673162165.pdf
    • http://alemotta.com/resources/original/file/96156333263.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/mimnt0f00f902vptivu4oj0230/22289155241.pdf
    • http://zamel2.pl/userfiles/file/44061644936.pdf
    • https://deltagroup.bg/uploads/file/71028445146.pdf
    • http://www.bluewhaleline.com/image/upload/File/zavifagepujifosi.pdf
    • http://oio.cn/uploadfiles/files/vuwosesutog.pdf
    • http://sattamatkapatti.com/userfiles/file/26119385662.pdf
    • http://autoset66.ru/admin/ckfinder/userfiles/files/43245244761.pdf
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606dbec5bbcc4---nitotalifarafexena.pdf
    • https://harkakotony.hu/UserFiles/file/pavugifetepozikagaw.pdf
    • https://www.movingwithmagna.com/wp-content/plugins/super-forms/uploads/php/files/b395979fbd04dfa3ebf622a6031ac033/81201067894.pdf
    • http://elite-weekend.com/clients/9/94/945a7f92a07ecc721aac768ad340748a/File/lebafusotopimofo.pdf
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608bca3b258b8---15925214412.pdf
    • https://mrmobilewebsite.agency/wp-content/plugins/super-forms/uploads/php/files/5623e9471cb9b2a45713debda4ba3de9/44115070155.pdf
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/ae4f1035dee6c7201e47e2b69f2dd7ad/60800489312.pdf
    • http://kaies.cn/upfiles/210525185929940235y9zfct.pdf
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160afb6d79e5a5---52769363140.pdf
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/45bfa999e1fb4263881dfdfa68c243b5/muvivopubotujumipexok.pdf
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/160861700472a5---49219688435.pdf
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc03f90670a---85783549462.pdf
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16082af2ed54fb---30429083880.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=sweetheart+stout+black+and+tan
    • 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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee25.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE25 16792 bytes
font_01_sfnt_off0001063c.bin
1729652808e85e3ce405bd3f8c7e2a15b21bdf43e6cc5c03b98b0f6f77abc56a
pdf-font-stream PDF embedded font (sfnt) at offset 0x1063C 10868 bytes
font_02_sfnt_off00011f61.bin
8b9e8f72c95ffdcef4ca241f6fd775f5f8ba55410799517b7a1f25abd8233e46
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F61 17724 bytes