Malicious PDF — malware analysis report

Static analysis result for SHA-256 4881b8b6606a0433…

MALICIOUS

PDF

79.0 KB Created: 2021-09-18 09:21:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 81643142667719265b2e5fb2edc2f792 SHA-1: 58b34c8c8e3083f9910755755c57dad8994da5db SHA-256: 4881b8b6606a04333cc11e7ce69d85e1913fd3a8ffa19a31ae6b53e8e359749d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are hosted on compromised CMS uploads, indicating a link farm designed to redirect users to malicious sites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution.

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://drafthe.ru/uplcv?utm_term=itext+edit+existing+pdf PDF link annotation
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130d12ab7cf2---71409418176.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/0eb4711b1d08d0201c59f53e97097de1/7583247141.pdfIn PDF document text
    • http://devitohomesorlando.com/userfiles/files/povigoxo.pdfIn PDF document text
    • http://evevoyance.fr/adh/.-/file/83155447976.pdfIn PDF document text
    • http://zekejozsef.eu/FCKfeltoltott/file/14228930853.pdfIn PDF document text
    • http://travelci.ru/ckfinder/userfiles/files/63982648294.pdfIn PDF document text
    • http://omonetach.pl/foto/ilustracje/file/tiliwarufajitanizub.pdfIn PDF document text
    • http://studiotecnicolari.it/userfiles/files/34487016323.pdfIn PDF document text
    • https://hung168.tw/UserFiles/files/janamofilupekefugawikaba.pdfIn PDF document text
    • http://classicalgardenstatues.com/uplds/file/96530626602.pdfIn PDF document text
    • http://leruichem.com/upload/files/77016793997.pdfIn PDF document text
    • http://brilliantsolarpaneling.com/userfiles/file/87804690705.pdfIn PDF document text
    • https://pbchistoryonline.org/uploads/file/9687081276.pdfIn PDF document text
    • http://www.fonfe.com/uploads/files/xuver.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/gs8q3arochhfa7fmvaqmk1rj0v/38212823912.pdfIn PDF document text
    • https://led7.ru/file/76694662187.pdfIn PDF document text
    • http://uts.edu.co/portal/app/ckfinder/userfiles/files/68457862344.pdfIn PDF document text
    • http://luyenthidhcanhsat.com/Images_upload/files/66472130713.pdfIn PDF document text
    • http://jeansresource.com/js/ckfinder/userfiles/files/jefazit.pdfIn PDF document text
    • https://angem.fr/userfiles/file/kabunexixivaboridadibok.pdfIn PDF document text
    • http://argyleliquidations.com/userfiles/files/xigabepikatemiko.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_off0000d0f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0F3 17936 bytes
SHA-256: adaaf8fc0e33db5b778a3a23d7d1d384e8babf498054997476a1d9d869f24c52
font_01_sfnt_off0000ffb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFB0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000117c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117C7 10296 bytes
SHA-256: f1fd0c9df553500c2dc00fdffd737363775112747887724c430ebc0c4ebdb468