Malicious PDF — malware analysis report

Static analysis result for SHA-256 545bf7233eea2f0a…

MALICIOUS

PDF

87.5 KB Created: 2021-06-26 01:08:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 59bc87936aa235f0f58f946a2e3d6881 SHA-1: 75fad1ae72155ccf7edf7ebe1e2576edd54791ef SHA-256: 545bf7233eea2f0a5d05f46a51ec8b1f3616ebc45d9871fb99bbfb12f0a02702
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a link farm pointing to multiple websites, many of which are hosted on compromised CMS upload directories. This suggests the document is designed to redirect users to potentially malicious sites, likely for phishing or malware delivery. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160828010ec0b1---34408893170.pdf
    • http://www.buildingmalawi.com/images/uploaded/documents/99147378773.pdf
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/9dfb7f9b738b4675deaf367aebc3ddd6/rirozatigavaronalexiguvix.pdf
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607daac056ea6---90344570595.pdf
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbb9959e6d---berisavalibunesavuxak.pdf
    • http://xn--3e0b556bhrbowi6undva.com/ckupload/files/nakalerinejenomika.pdf
    • http://caopump.com/admin/userfiles/file/30584140351.pdf
    • http://zeminyerkaplama.com/upload/ckfinder/files/vewasibemebe.pdf
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c74a753def7---gupokeputewanudipav.pdf
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16082d303e7f89---dolorazikikaj.pdf
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/09d7d37b13d475d5de827d717a76a76d/fisofenorizemiwavuxekib.pdf
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/6d57cbe7ec1fdc43f5e5ab01d88c2823/35012153549.pdf
    • http://sklepjola.pl/userfiles/file/75960480046.pdf
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/3fb7c18378fb8a3a1a8b08fa2657ddfe/bukiwax.pdf
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/1607ed20b530fa---pusasavijusenu.pdf
    • http://www.awakohchang.com/image/upload/File/afowub.pdf
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1606d572763727---radururimivov.pdf
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/bupt2c7r545jqbeuhdmc0mubo5/doziwufakunavokaminosebim.pdf
    • http://coumert.com/images/file/47601938194.pdf
    • http://unityproductions.com/upload/files/gazosomakusezava.pdf
    • https://xanbiente.de/userfiles/file/sexupizag.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=276+divided+by+3
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608474db4ae73---defebipebewowunofozas.pdf
    • 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_off0000f135.bin
03ed2a60b2f4d9fe03b8ef4b56c40077f820bb0f28cc7c0583f591bc39f599c4
pdf-font-stream PDF embedded font (sfnt) at offset 0xF135 18452 bytes
font_01_sfnt_off0001223b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1223B 16792 bytes
font_02_sfnt_off00013a52.bin
f20c56139f8dfc1c300fb310e613cf5bd8819de772d8cd83ef4e081125115fa8
pdf-font-stream PDF embedded font (sfnt) at offset 0x13A52 10176 bytes