Malicious PDF — malware analysis report

Static analysis result for SHA-256 90e523afa0d20fb3…

MALICIOUS

PDF

71.1 KB Created: 2021-09-06 04:57:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-17
MD5: 087c7bcd7be01625d3c93b2e72b0f1d8 SHA-1: 527ae762612bb444699e1ceb64e28c19058c1fe1 SHA-256: 90e523afa0d20fb3863a788664938e30bc8c04d6f64f91c356b7ec5c8845a498
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to potentially compromised CMS upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent. The primary function appears to be acting as a link farm to distribute further malicious content, likely via spearphishing attachments.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://closehorses.com/userfiles/file/74339078488.pdf In PDF document text
    • http://www.deep2001.com/images/library/File/bomumivuzu.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/a058f45de871f23dbba9c1d96e73829a/37605515071.pdfIn PDF document text
    • http://17njl.com/userfiles/files/xafusexofupidorikemurito.pdfIn PDF document text
    • http://fouladsazanco.com/Upload/file/55607863787.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/1608110a6832f9---13907434141.pdfIn PDF document text
    • https://brigitte-farner.ch/userfiles/files/pokafuwerisogusezatibub.pdfIn PDF document text
    • http://asiavent.com/UserFiles/file///semelop.pdfIn PDF document text
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/c55e0ddf59f231e4353ab4af7e45089f/84341039642.pdfIn PDF document text
    • https://tolgyesvolgy.hu/userfiles/file/zofusaranutop.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/nitikefulititer.pdfIn PDF document text
    • http://banghetretunhien.com/media/ftp/file/mibabagafunosizin.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135418264515---32371612480.pdfIn PDF document text
    • http://eiak.org/upload/editor/files/fegarejuwuxagaba.pdfIn PDF document text
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/41260b1293001041502a3353e55caf8c/pirabagalobirupamakog.pdfIn PDF document text
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160718e470aacc---24494483311.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/a513146a1f1048a6d0177301919fda79/zofag.pdfIn PDF document text
    • https://www.scmsgroup.org/ckfinder/userfiles/files/jemizifagedawodeku.pdfIn PDF document text
    • http://ipceurope.com/assets/file/tipofede.pdfIn PDF document text
    • https://conexusinternational.com/ckfinder/userfiles/file/pumisu.pdfIn PDF document text
    • https://australiancaravancentre.com.au/application/third_party/ckfinder/userfiles/files/wojov.pdfIn PDF document text
    • http://hongpakthai.com/ckfinder/userfiles/files/zagizomevataneboluxenizel.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/5b4827efc0a0c8f298019bbd13b545f8/37857340604.pdfIn PDF document text
    • http://sbairs.com/datas/files/lurifabowasedoguzuvenetin.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=km+to+miles+chart+pdfPDF 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_off0000b655.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB655 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE67 15628 bytes
SHA-256: 5c33712aabb981e4abd2604161bae505aa04bf6499ae83e4a88a8b40f6cd204c
font_02_sfnt_off0000f64b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF64B 10772 bytes
SHA-256: cd9db4818c55d217b5be784300a509b4d7de0c2cf82bda25d92566c095e685ac