Malicious PDF — malware analysis report

Static analysis result for SHA-256 1140559cd66ed847…

MALICIOUS

PDF

74.2 KB Created: 2021-09-20 13:37:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 32f3a46270e8ac2b98fef0bf7443d27c SHA-1: c5888601d6801948115bbb0e905abe4eae73bbb3 SHA-256: 1140559cd66ed847b414cb5f1bfcf6a13a8b9ced3ac6cb594325e90e11dc5ad8
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 CMS upload storage or are part of a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware sites. The embedded JavaScript suggests an attempt to execute further malicious code.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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=chai+romantic+shayari PDF link annotation
    • http://savvyais.com/userfiles/file/68326998996.pdfIn PDF document text
    • http://sure2trips.com/bot/ckfinder/uf/files/70833655258.pdfIn PDF document text
    • http://sherwoodchambergolf.org/ckfinder/userfiles/files/39592054529.pdfIn PDF document text
    • http://foxgraphics.paulsfashion.in/files/terafutekemikixafex.pdfIn PDF document text
    • http://lepal.sk/ckfinder/userfiles/files/gavetubevijal.pdfIn PDF document text
    • http://countryclaim.cz/userfiles/file/pizaje.pdfIn PDF document text
    • http://thesciencenetwork.org/uploads/files/92834126803.pdfIn PDF document text
    • http://medicare-darmstadt.de/bilder/UserImages/file/45834215154.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/16145323748e61---63015739197.pdfIn PDF document text
    • https://amigo-shop.105h.net/upload/files/kufit.pdfIn PDF document text
    • https://www.travelknowhowscotland.co.uk/assets/js/ckfinder/userfiles/files/piluvupo.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/hiqoe62q7udimejkjp6rn1ihsn/24971780539.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16131b7b844d45---83328822584.pdfIn PDF document text
    • http://dbexpertise.fr/catalogue_dynamique/file/75991253046.pdfIn PDF document text
    • https://candica.pl/ckfinder/userfiles/files/11324152141.pdfIn PDF document text
    • https://fond.ru/userfiles/file/vizedizokezotakarisedu.pdfIn PDF document text
    • http://hanahana.vn/media/ftp/file/luborururibowasamod.pdfIn PDF document text
    • http://www.espace-hotelier.com/ckfinder/userfiles/files/ligufudu.pdfIn PDF document text
    • http://gs-metals.com/filespath/files/20210901101813.pdfIn PDF document text
    • https://aimtronu.org/userfiles/file/68355172197.pdfIn PDF document text
    • http://spynet.gr/Administrator/uploads/userpics/OutPostImages/files/44621141545.pdfIn PDF document text
    • http://hotechike.com/files/files/77819345941.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_off0000bbae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBAE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d3c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3C5 10464 bytes
SHA-256: 55d21941747a37e4c12810a4a5844c663f4e2841d7dc22620f9ca8403c1922dc
font_02_sfnt_off0000eb68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB68 18552 bytes
SHA-256: 09b422a0a2d732e734e8beda77ad088290a7817bd03a96080c5164dba5099160