Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca907b9fff34588a…

MALICIOUS

PDF

81.6 KB Created: 2021-07-04 07:46:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a5ee456cf5a27fd738ec9bec50ef6987 SHA-1: 9dc11e0b2ef3e4cf3aebc6579a5adf2d008a572f SHA-256: ca907b9fff34588acfac86d9071874d1f0820b0c68ac99134e214f4b8d7f72f6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Numerous embedded URLs point to various domains, many of which are associated with compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to contain metadata rather than user-readable content, reinforcing the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://wastran.ru/uplcv?utm_term=absolute+of+a+number
    • https://leavingcare3plus.ch/userfiles/files/vosotejifix.pdf
    • http://ahdongjiu.com/upload_fck/file/2021-4-29/20210429210900459930.pdf
    • http://robwalker.net/fckupload/file/6733959294.pdf
    • https://arvikabc.com/images/uploadedimages/file/xirisegidava.pdf
    • https://fnb-concepts.com/images/uploads/files/devizosibuz.pdf
    • https://xanbiente.de/userfiles/file/11969097540.pdf
    • https://thetitangroup.ca/wp-content/plugins/super-forms/uploads/php/files/730e89fff52d362478f49bdd64df26e7/77320629269.pdf
    • https://artbynela.com/uploads/file/35275305650.pdf
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160849d1ea6f97---86993117725.pdf
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ddf17385193---sawexovepuzolavotefake.pdf
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/4196d49cfcc06768ec8b96ae7ee394af/44021415885.pdf
    • http://whscardinals1963.com/clients/9/9e/9e5fab02d16e7113a74bdd4e7828f974/File/31090840467.pdf
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/0vroh6btgl6fsmqomckppeu1vr/60940500294.pdf
    • https://scavilecis.it/userfiles/file/73802290825.pdf
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/0c64c2e5966b38a37af29a464c360ed0/98178563855.pdf
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a385a1df555---49385052679.pdf
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/01aa1dfbc8e751a70664bec90f3c1442/wedolamukovazokawusapez.pdf
    • http://kcde.kr/userfiles/file/57467336936.pdf
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/vaf9g1o5bpb1502cak4o3tnmg0/48962858466.pdf
    • http://erictex.com/ufiles/files/nolora.pdf
    • http://lasfyy.com/uploadfile/file/20210704015439794.pdf
    • https://bodwellassociates.com/wp-content/plugins/super-forms/uploads/php/files/7ed6b42d7d40d66e105b8ccb4aa4254b/42579365459.pdf
    • http://zuche0551.com/upload/file/5466001133.pdf
    • http://terapeutickemasaze.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b2092ceb771---29326169176.pdf
    • https://www.engltg.com/wp-content/plugins/super-forms/uploads/php/files/d798fdc8fc291fbbc0b33b17f5862fa5/77116741708.pdf
    • 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_off0000da99.bin
2c0b705f9e266cf72e9ea80538a873178a5a4afc88d6a2b4478f7fcebbf85305
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA99 17212 bytes
font_01_sfnt_off000107cc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x107CC 16792 bytes
font_02_sfnt_off00011fe3.bin
691ef34b3ff9291011651809d9185f10daaec17db15115b2c30b7502cc3b25be
pdf-font-stream PDF embedded font (sfnt) at offset 0x11FE3 10504 bytes