Malicious PDF — malware analysis report

Static analysis result for SHA-256 a639d8e542f3276c…

MALICIOUS

PDF

82.4 KB Created: 2021-09-07 22:57:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: d737d516d11e5ac1d7350b1bf8afa09c SHA-1: 3a683b89a901e3d5a4e70a08d3ab7bb4b5303d93 SHA-256: a639d8e542f3276cf7f492a945ccf939937fdc0a91f9139aa7f56c261f13c731
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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 http://karmand24.ir/basefile/ehotel724ir/files/18810474587.pdf In PDF document text
    • http://uro-medical.pl/zdjecia/fotki/file/xugibagurogulojoruzowe.pdfIn PDF document text
    • https://afayl.com/userfiles/file/kokipewot.pdfIn PDF document text
    • http://sgd42.ru/userfiles/file/gozesi.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134166c46fcd---78171573925.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607d9dad45ef1---xekonugatekujajonomabewu.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/c76c6e595e18a11e1f0e30d5ecd20083/84224365515.pdfIn PDF document text
    • http://koreaseals.com/ckfinder/userfiles/files/38637228434.pdfIn PDF document text
    • http://prime42.ru/userfiles/files/97759968252.pdfIn PDF document text
    • https://laplacedesstores.com/upload/file/96261529740.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/3fa40a28747ecbd6b54313207f0d5243/zatojew.pdfIn PDF document text
    • http://platypusspot.org/uploads/ckfinder/userfiles/files/kezap.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/160990121510e6---76070539918.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/16082fc44d5644---36952612526.pdfIn PDF document text
    • https://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/fcb04e31f952fb71f317905b59f097b2/83332678544.pdfIn PDF document text
    • http://safedoorsystems.com/cmsimages/file/9994976892.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/109d1feda900b4c7ea1ee93c79432ea2/xavosofiwavifapowupem.pdfIn PDF document text
    • http://harchovyk.com/userfiles/file/somapiv.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/16126ef9487029---95627992443.pdfIn PDF document text
    • http://dongphat.net/upload/files/rabuwazaguxitefa.pdfIn PDF document text
    • https://congchung7.com/upload/file/fimojebafosefa.pdfIn PDF document text
    • http://urbanposthotel.com/admin/ckfinder/userfiles/files/74055251732.pdfIn PDF document text
    • http://brilsports.ro/userfiles/file///wofefazedit.pdfIn PDF document text
    • https://bursac.net/userfiles/file/74728738820.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160ba82194beab---durezagukedavosezaxutogad.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/gosugira.pdfIn PDF document text
    • http://decom.pro/admin/ckfinder/userfiles/files/25343026107.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=industrial+catalysis+jens+hagen+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_off0000d53e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD53E 11076 bytes
SHA-256: b4364c94095b1c8511556308c6dfe751b91827be7fdb0b8a38a271532476760d
font_01_sfnt_off0000eec3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEC3 19188 bytes
SHA-256: 40d1748feb9ff2881044b5b295fbc38fa7d428be0f08bfe344283c5da6c8ca96
font_02_sfnt_off000121da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1