Malicious PDF — malware analysis report

Static analysis result for SHA-256 28344c61fd412fc2…

MALICIOUS

PDF

69.5 KB Created: 2021-09-06 00:57:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 1ef3924ba925f58d80a76dfbaf7fa88a SHA-1: d293b157789ad5cb6c8d64baf9885919dd5988ed SHA-256: 28344c61fd412fc279b8f2f1778b43624ba573f3743ea15503f6ce7925673293
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed for malicious redirection. The ClamAV detection and ML classifier strongly suggest this PDF is malicious, likely attempting to exploit vulnerabilities or redirect users to phishing sites. The embedded JavaScript is a common method for initiating exploits or downloading further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://marljivo.hr/userfiles/file/saxezijixigekij.pdf In PDF document text
    • http://bantinnhadat.com/users/files/73980090232.pdfIn PDF document text
    • http://www.celso.org/download/54290429108.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/eb9226541f2b5a16e61b769282bfe027/vixipapomaxuxosojizesab.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/v7607lbouq0p8s99b3167e4903/fubilafeduvusewobabirer.pdfIn PDF document text
    • https://anjingliar2.com/contents//files/77744022245.pdfIn PDF document text
    • http://aucoindeshalles.com/menu/file/fuzinikejarej.pdfIn PDF document text
    • https://machinex-machines.com/UserFiles/File/25825139811.pdfIn PDF document text
    • http://lizhechem.com/upload/files/misuralugotobebilunojoraj.pdfIn PDF document text
    • http://dmhu.eu/uploads/uplib/file/misijesobodizafode.pdfIn PDF document text
    • http://britishcytology.org.uk/ckfinder/userfiles/files/34082971838.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078021b2380d---xudabatoxuvidus.pdfIn PDF document text
    • http://ahchala.com/img/file/wadoz.pdfIn PDF document text
    • https://aronabritcan.com/userfiles/file/moratilidilumodusoduj.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/0g3l9puh6deqt91jdu1jiocq5d/xekevibekikudowenizoli.pdfIn PDF document text
    • http://frangarcia.eu/upload/file/26776123653.pdfIn PDF document text
    • https://ottopianos.nl/files/vajozifog.pdfIn PDF document text
    • http://acmemask.com/upfiles/editor/files/36055569222.pdfIn PDF document text
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c246e1dc2e2---demomuz.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a8bce47b0e---josuxojuxupekamu.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/16077137706c37---gapufe.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/8747d94e0e4a65504717b487b9e280ae/kevulin.pdfIn PDF document text
    • https://rosedreamholidayhomes.com/ckfinder/userfiles/files/38549001832.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=maths+worksheets+for+1st+gradePDF link annotation
    • https://grupo.iberia.com/js/ckfinder/userfiles/files/14692514024.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b35b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB35B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB72 10616 bytes
SHA-256: a92cf8571882bd3def266f16902e4c5cbc969890168f6f112e91ef243fc60516
font_02_sfnt_off0000e3d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3D1 14420 bytes
SHA-256: 0ad141195c560f96bdd45195704b6c9d007e8970e0477ae0ddde03117dad8459