Malicious PDF — malware analysis report

Static analysis result for SHA-256 a63f7291f93f921e…

MALICIOUS

PDF

110.8 KB Created: 2021-09-03 00:07:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: a8939dac1a0cc79c43f539375095cb8a SHA-1: 65743bf17b9c5a21be2f8abe6dc8e74d994ad452 SHA-256: a63f7291f93f921eeaa1ed869d7fdcd15a6b2423a902111c840740fe9ecd7f75
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://krisoc.ru/uplcv?utm_term=environment+pollution+paragraph+pdf PDF link annotation
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/b357b28505668996320fdec422dd3fd8/sajuxonet.pdfIn PDF document text
    • https://www.harnoordesigns.com/wp-content/plugins/super-forms/uploads/php/files/1sue3m5lfv7pnagpe70nie0ve2/nikosilileruv.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606cdd3cd5835---dapiwuveditijoxuf.pdfIn PDF document text
    • https://keralatemples.info/ckfinder/userfiles/files/gatitegutufedafuwaginefal.pdfIn PDF document text
    • https://10glazsikeyrosa.ru/file/veluxafas.pdfIn PDF document text
    • http://ros.by/ckfinder/userfiles/files/21554500543.pdfIn PDF document text
    • https://cape-electronics.com/media/file/kiwiv.pdfIn PDF document text
    • http://stuarteisbrucklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/patanewudik.pdfIn PDF document text
    • http://xinghui.co/upload/ckimg/files/202108240007129721.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/d2p36l89cq0b50am62fk0o8bor/46485674919.pdfIn PDF document text
    • https://actor-conseil.com/files/file/rirulobuxulusimeru.pdfIn PDF document text
    • http://acecaalcoy.com/userfiles/file/foxulavozixulukegepibasup.pdfIn PDF document text
    • https://retrofitoman.com/ckfinder/userfiles/files/18902214456.pdfIn PDF document text
    • https://birgatour.mn/js/ckfinder/userfiles/files/5519544014.pdfIn PDF document text
    • http://www.ocptecnology.com/admin/uploaded/fck/file/mimekupazetewevezosoponem.pdfIn PDF document text
    • https://www.mysmilestudios.com/wp-content/plugins/super-forms/uploads/php/files/96dc4cce9872a52723046862f217667d/84393058468.pdfIn PDF document text
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/160881577d95ad---dokaximujizavemoxi.pdfIn PDF document text
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/b55cd6404f7045053dd9d6926e2ea79d/dizek.pdfIn PDF document text
    • http://ogbchurch.com/clients/880797/File/jebazajutegosazila.pdfIn PDF document text
    • http://umhouses.com/uploads/files/duvuzudujilulikojatej.pdfIn PDF document text
    • http://janyska.home.pl/_mjanyska2013/fotki/file/pidoravoneze.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_off00014ab7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14AB7 10924 bytes
SHA-256: 94aefa149ba481248796b6bcae2cbedb2b1c2e0cd6f81a0ab988af80c08c3761
font_01_sfnt_off00016395.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16395 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00017ba7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17BA7 18672 bytes
SHA-256: 8afa9e5f83c79134c2dbc17251766e14bf7fe8c65b404a4db16be7f78407de4a