Malicious PDF — malware analysis report

Static analysis result for SHA-256 c618539ba361c416…

MALICIOUS

PDF

75.6 KB Created: 2021-10-03 21:38:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cab7399a66d69be5be0d55ff1289c1a9 SHA-1: d0fb9de54f8c0b8a45e40dfa3a7a4ca36009ddc5 SHA-256: c618539ba361c416a2046b6250fb0cca168c994c59000e6f644b571dc32322ef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress upload directories and disposable hosting, indicating a link farm designed for redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a phishing or redirection attack, potentially delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161448e4ebe89d---rapivefonuvogofidebenesel.pdf
    • http://www.vegagastro.pl/upload/file/kolel.pdf
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141ab1356be4---25768710371.pdf
    • http://php-lounge.de/userfiles/file/puwafuwogezovumelukesavo.pdf
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/16130ee68728a6---dozokeguran.pdf
    • http://giadinhmedia.com/uploads/files/65928936421.pdf
    • http://commune-bourre.com/userfiles/file/23125427505.pdf
    • http://mastera-mix.ru/ckfinder/userfiles/files/jikapukudabap.pdf
    • https://www.ijdsir.com/ckfinder/userfiles/files/45961480631.pdf
    • http://mskgroup-spb.ru/upload/file/lipekufopi.pdf
    • https://contabil-fiscal.ro/mm/file/36069895421.pdf
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16156382b70897---koxejomixudepawasugulo.pdf
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/mojita.pdf
    • https://morganmethod.tuesdaytrader.com/ci/userfiles/files/57554096963.pdf
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/2subafogv53lq0u5vvs1nio685/molasivaw.pdf
    • http://standardamulet.com/files/files/73181576728.pdf
    • http://yakutiaprime.ru/SITE/files/editor/file/vodelubajinekagezolos.pdf
    • http://congtrinhnhaviet.vn/upload/files/zezemamubumuselomofove.pdf
    • https://jmclimatizacionhvac.cl/images/subidas/file/72417343582.pdf
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16155ebe9094e3---30563080803.pdf
    • http://sochi-polyana.com/ckfinder/userfiles/files/61900341274.pdf
    • http://nifaelectronics.com/userfiles/file/33050343577.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=area+of+reinforcing+steel+bars+table
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000be10.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBE10 16792 bytes
font_01_sfnt_off0000d627.bin
99b1154802930691324ccb3c0574d94207680319b4b07b3558fffad7e5b67556
pdf-font-stream PDF embedded font (sfnt) at offset 0xD627 10632 bytes
font_02_sfnt_off0000eea1.bin
3b09cc7d891c18aca9f4186e45ecc6b8a0e0ad9ff0a48463fde67233b27b09a7
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEA1 18684 bytes