Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a3e6217762b49d8…

MALICIOUS

PDF

74.7 KB Created: 2021-09-30 12:15:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 05cb4240f15507c78081a19e038f1d21 SHA-1: 8c6ff96d92c36dd9fa0ee5c8edb6fd4510fc146b SHA-256: 8a3e6217762b49d8ca0b4bf6a022db242b24cdea6e271ef1a8f22069d96fb76a
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised websites, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent. The embedded URLs are likely used to redirect the user to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://trieuduong.com/images/Download/gerigarasipuz.pdf In PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613de897e6c6e---kenafokaruwapukopumi.pdfIn PDF document text
    • https://rajakeempat.com/contents/files/33122458062.pdfIn PDF document text
    • http://pkpneu.cz/userfiles/file/pudazonokob.pdfIn PDF document text
    • http://pileshoppen.dk/userfiles/file/66866869981.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161431ddad5856---83622850282.pdfIn PDF document text
    • http://etalentlink.com/uploadfile/file///2021090903054570.pdfIn PDF document text
    • http://ehomerealestate.org/images/file/lanesazugoju.pdfIn PDF document text
    • http://turismo-usa.com/files/others/74216195744.pdfIn PDF document text
    • http://altronic.pl/!mag2011/userfiles/file/4791334480.pdfIn PDF document text
    • http://fiumaradelsossio.it/userfiles/files/39637045679.pdfIn PDF document text
    • http://www.euro-fly.eu/userfiles/files/87864028689.pdfIn PDF document text
    • http://thebankcardservices.com/uploads/files/ruwago.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/577mtf34hq0e9qeafs1eob0fb7/kamunapevogipuxikulux.pdfIn PDF document text
    • http://karimeh.com/public/userfiles/file/16697700221.pdfIn PDF document text
    • http://namlinhchivietnam.net/userfiles/image/file/47583192112.pdfIn PDF document text
    • http://aurastaffing.es/upload/file/2356488619.pdfIn PDF document text
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16149797eab9a6---mifodis.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614eff05a4914---27187799198.pdfIn PDF document text
    • https://resttour.com/images/userfiles/files/52449658131.pdfIn PDF document text
    • http://efrex.cz/files/file/76538416687.pdfIn PDF document text
    • https://kawanmto.info/contents/files/5944698185.pdfIn PDF document text
    • http://daedukgs.com/admin/fckeditor/data/file/20210924184534.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=install+android+on+lumia+540PDF 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_off0000bc69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC69 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d47b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD47B 18792 bytes
SHA-256: 1b501d1836065043ad2f5c472fea4d67ceec06ec16ddfcdf7e9dcce5b7348929
font_02_sfnt_off0001052a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1052A 10660 bytes
SHA-256: c4e81be5c1ed64195b868daa26a3e1a248d4e50ab84ece1f37a57295b140d857