Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6c05c61f0aa413a…

MALICIOUS

PDF

80.4 KB Created: 2021-09-03 11:06:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 83642e62657777166ac5543142b5784e SHA-1: 51fcfcf23364adb98583549bc422999154fe9fc6 SHA-256: f6c05c61f0aa413a764d6235d39b72be57c83f70774596495addf508e7df715b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to numerous external URLs, many hosted on compromised WordPress sites, suggesting an attempt to distribute further malicious content or conduct phishing. The ClamAV detection and ML classifier strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/mii76sj9f5r84h8uear96c0kg6/zefep.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a764a91e1a---29318935187.pdf
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/16084550614ebc---94809091105.pdf
    • https://irrisyst.eu/files/file/28652241364.pdf
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096dcb5b199d---boxaxokefozogaxewebosab.pdf
    • https://industriameccanica.it/file/52627907300.pdf
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/0959d6f3c8842a2c16534b4899680cf8/59800192604.pdf
    • http://matras-devison.com/upload/file/retesoxiluviromu.pdf
    • https://anfauglir.com/images/file/66069227618.pdf
    • http://www.fan-consultants.com.tw/ezadmin/ckfinder/userfiles/files/pupejedazawupe.pdf
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16072703a78325---bapujeje.pdf
    • http://teleinwestor.com/userfiles/file/2571585404.pdf
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/29a797ddac885af140ed8a51ba803037/luwilifa.pdf
    • https://almondzwealth.com/administrator/imagetemp/file/kurevezar.pdf
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608fad508cda0---gaviwuk.pdf
    • https://vaitinhdien.com/app/webroot/upload/files/saserivadofiso.pdf
    • http://thevenetianmask.com/clients/71561/File/18426910322.pdf
    • http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160722b976f5ae---57832190988.pdf
    • http://lisaarkinlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/46309866805.pdf
    • http://karthikeyanjayaram.com/userfiles/file/63016490098.pdf
    • http://mdbim.pl/ubezpiecz/obrazy/file/wojaduvujaja.pdf
    • http://perechen-jurnalov.ru/js/ckfinder/userfiles/files/38311816974.pdf
    • http://psychoterapia-przemysl.net/img/userfiles/file/97615063835.pdf
    • http://letdentalab.com/img/files/vakawovotapux.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=finding+interior+angles+of+polygons+worksheet
    • 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_off0000d1ec.bin
7b375a84c0211a70db1a2f093356bf16825b5b4e149590a6230e53e0c8b4001d
pdf-font-stream PDF embedded font (sfnt) at offset 0xD1EC 18676 bytes
font_01_sfnt_off000102c4.bin
49a5c0608dce450b6f0491acf7ed4476ffe9543739f831faaa2628f96477eae1
pdf-font-stream PDF embedded font (sfnt) at offset 0x102C4 11048 bytes
font_02_sfnt_off00011c40.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11C40 16792 bytes