Malicious PDF — malware analysis report

Static analysis result for SHA-256 670e0fa56f833d49…

MALICIOUS

PDF

80.1 KB Created: 2021-09-12 22:30:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 901fdc0d41068df801577b510388a2d7 SHA-1: 3912dbc120d9b0177e6696ee3ed3bb1761301c74 SHA-256: 670e0fa56f833d4962cecc6a04eee9ce665ed10d9e525a014100e15d04d759e4
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The presence of a compromised CMS upload link further supports the malicious nature, likely serving as a lure to download further payloads or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://xn----8sbemnkjd7bfu.xn--p1ai/design/img/upload/file/sakeronipevugut.pdf In PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/5slk8hdluhpu03re1novihff8b/5300741149.pdfIn PDF document text
    • http://www.enredmail.com/templates/files/idCliente_/file/vitefekotafagizigalurotex.pdfIn PDF document text
    • https://zoorichi.com/temp/fckeditor/file/23923935265.pdfIn PDF document text
    • https://thuhuonglacquer.com/uploads/news_file/safejekanubimuki.pdfIn PDF document text
    • http://sportsclinicwest.ie/media/contents/file/81693759968.pdfIn PDF document text
    • https://www.auto-ecole-rive-droite.fr/ckfinder/userfiles/files/8297352101.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613da86af2f13---99914266548.pdfIn PDF document text
    • https://foodsafebox.com/ckfinder/userfiles/files/mepinozaredijelena.pdfIn PDF document text
    • https://china-glass-mosaic.com/userfiles/files/20210902_080521.pdfIn PDF document text
    • https://melnikhouse.com/userfiles/file/73208600984.pdfIn PDF document text
    • http://stolizstekla.ru/userfiles/file/14039260730.pdfIn PDF document text
    • http://tsrmmessina.it/userfiles/files/diwudizebepujiv.pdfIn PDF document text
    • http://0048.pl/48files/file/terig.pdfIn PDF document text
    • https://maychieuvinh.vn/upload/files/5975556994.pdfIn PDF document text
    • https://aradovan.com/userfiles/file/97488373401.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16131c25c1fa54---42722939295.pdfIn PDF document text
    • https://bauarch.bg/files/97811642632.pdfIn PDF document text
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/0387eca9ac538ed02568ce3beba59a27/tonetovebez.pdfIn PDF document text
    • https://www.iieng.org/editor/ckfinder/userfiles/files/dafetakesigo.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16130054b34d9a---24940243749.pdfIn PDF document text
    • http://client.diffuse.info/files/wumowepaniwevisug.pdfIn PDF document text
    • http://www.everhouse.lt/wp-content/plugins/formcraft/file-upload/server/content/files/16136e6e8c01af---2943296519.pdfIn PDF document text
    • https://soosekszer.hu/upload/files/tisonesu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+mod+terraria+mobilePDF 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_off0000d549.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD549 10356 bytes
SHA-256: 7c1ef3e03cee95e086265baab031a52cb8c35e04eb07af6c688fba0f21ae9812
font_01_sfnt_off0000eca5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECA5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000104b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104B7 17740 bytes
SHA-256: abc99db30a9e61db79229af9e8ae3c7fa4e0753f5c2cb72dff0854837404adae