Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a75bc9d3094afce…

MALICIOUS

PDF

77.2 KB Created: 2021-09-01 09:16:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 0de356b065291db6a5af8753db685867 SHA-1: 621dc90cc425cd68980e30705b3b55a1d4e48e09 SHA-256: 5a75bc9d3094afcec13fbcd29bc45bd30df21859e24d54bf36eb30f35e25e641
156 Risk Score

Malware Insights

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

The PDF document was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple compromised or disposable hosting sites, likely for phishing or malware distribution. The embedded URLs and the nature of the heuristics strongly suggest an attempt to exploit users through deceptive links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://guides2alpes.fr/uploads/file/41648527929.pdf In PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/1610f3b0cbbbc4---kuvodufuvul.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fd53fd74d2---tojawuzefosopolilijaxidi.pdfIn PDF document text
    • https://nsck-cykelmotion.dk/ckfinder/userfiles/files/92264157495.pdfIn PDF document text
    • http://ranaghatpchsschool.org/userfiles/file/lunaxutimadojepurerofa.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/flpvkb9ueg7i45l4q9f5sculq7/xugijezuwiwu.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7c19855020---31759337528.pdfIn PDF document text
    • https://childconcern.in/trila/userfiles/file/tejub.pdfIn PDF document text
    • http://dichvuhangngay.vn/uploads/image/files/vosux.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c090ba62db7---fixekegejiwofudefuf.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/ib1vp9jn1ehgpcvqlkqklqhc6k/gopilafujitisulogijofekag.pdfIn PDF document text
    • http://dolphinegypt.net/userfiles/file/valalodeseg.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608610dc64c9a---13519870708.pdfIn PDF document text
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/61e84963a8620417cfa1e7abfefcc911/68653975536.pdfIn PDF document text
    • http://studiolegaletrotta.eu/userfiles/files/55792276298.pdfIn PDF document text
    • https://senesi-sklad.cz/userfiles/file/totofepuwosipuradolexox.pdfIn PDF document text
    • http://tubietelbar.hu/uploadfile/vopubafoxagozoxezalepup.pdfIn PDF document text
    • http://quickvideo.nl/userfiles/file/48093011932.pdfIn PDF document text
    • http://myagreement.com/UserFiles/file/8019469432.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608122e7e7213---59781271994.pdfIn PDF document text
    • http://bmcnx.com/userfiles/file/sutijevidiwevufupewezipi.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/ce28ca0d9bd6edaa4ca140e34d645238/53316663862.pdfIn PDF document text
    • https://opuntia.eu/wp-content/plugins/super-forms/uploads/php/files/220c7e37f8eecd2947feed9134bb5208/tuzefuterigare.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160985ff44d318---46118982584.pdfIn PDF document text
    • http://maidnheaven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cc276d0ae5---71854353511.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=apps+to+steal+wifiPDF link annotation
    • 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_off0000c87b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC87B 18396 bytes
SHA-256: 85c8b914941e46de6442cd24d89aeb22c80861eb66e0ffa24636b4989fce634e
font_01_sfnt_off0000f7ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7EE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011005.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11005 10212 bytes
SHA-256: 47be78de3dda0a687457329c92625d973b84678319803545a2e12afd04fead7f