Malicious PDF — malware analysis report

Static analysis result for SHA-256 83d72f786c41c7b6…

MALICIOUS

PDF

71.8 KB Created: 2021-07-22 09:07:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0796f19e143d754b7bb916f56f22af16 SHA-1: f094e557c12a41faa92c1cdda96744fc15c7efe1 SHA-256: 83d72f786c41c7b606343574be12d3e11c831ed9d0ee35d277c7b76f990f16a1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The numerous embedded URLs point to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious or phishing content. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160910324e3dc1---46967502438.pdf
    • http://longthinhphat.net/uploads/files/vedexotixaxokixemedo.pdf
    • https://dammesliepas.lv/ckfinder/userfiles/files/11974933891.pdf
    • http://savannahcentury.info/clients/4/44/449a5b3489ef279447e90cf6cdd72f1c/File/gulenunigezuved.pdf
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9b55ceeb09---68561962329.pdf
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160bfae3fe3f2b---82044663900.pdf
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/bpgccaobct7mq0mkuoiea933no/pabalelamajogumuwerutados.pdf
    • http://standartbio.com/fckfiles/file/41766864761.pdf
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/9c05217f6358bd4fce1063236065ac76/bipegalekujajofamefunelez.pdf
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/177dd9c5or6svogcghfh901pb9/gobafafogusemomotisozo.pdf
    • http://ongnuocdenhat.com/upload/files/kafotapunufexosoj.pdf
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16088b29eb1f33---81296406750.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081759fd3ef9---gafobotabozakov.pdf
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160759c97ef899---tomotagofijaluzupezumaper.pdf
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c26c9cb9ad---revesibimigedekakula.pdf
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096f81605fbf---tumewobokogutonogixufi.pdf
    • http://renknh.com/ckupload/files/34598418574.pdf
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/5286a9cd1c266f091fc5794b90eb0658/domod.pdf
    • http://caphegiabao.com/upload/fck/file/41845504695.pdf
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/fa4440e4ac927ab5b512f648c54056dc/93436436338.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=simple+is+sophisticated
    • 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_off0000b8d7.bin
b24453c30c404f55891b289ee288a0cef557e95c508dc25bb30a188924349820
pdf-font-stream PDF embedded font (sfnt) at offset 0xB8D7 10648 bytes
font_01_sfnt_off0000d132.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD132 16792 bytes
font_02_sfnt_off0000e944.bin
75d8f221f7645816fac52bc79d6879ad964c255fc07d7911e56ac37ae1aeb7d6
pdf-font-stream PDF embedded font (sfnt) at offset 0xE944 15996 bytes