Malicious PDF — malware analysis report

Static analysis result for SHA-256 3273a9eab18ba9b4…

MALICIOUS

PDF

84.6 KB Created: 2021-09-02 10:21:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 42f42c97421376b97d00cebd12ead1da SHA-1: 281d484576ba9e955b1ffcbdd72cda0ea106aa8f SHA-256: 3273a9eab18ba9b42ae04e2f22e0ad83a4376f84828e50b8e153cabae5b70acf
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Several heuristics indicate the PDF functions as a link farm, with many URLs pointing to compromised CMS uploads or disposable hosting. The embedded URLs, such as http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/16094578da1cfa---wiramidevivikedisivezob.pdf, are likely intended to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://linhngapt.vn/upload/files/92323879808.pdf In PDF document text
    • http://debsluxe.com/clients/1/17/174397649ed9f07baa8f9d9f48c72a4d/File/17161905562.pdfIn PDF document text
    • https://cnn-logistics.com/asset/files/fejabepelinanafo.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607bee09b60f0---67529160278.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/75594047306.pdfIn PDF document text
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160737a04506ba---sidugidirodomivumalezig.pdfIn PDF document text
    • https://biogenetixpharma.com/ci/userfiles/files/lugozowazexatumesameb.pdfIn PDF document text
    • http://palestraarkadia.it/userfiles/files/55958680166.pdfIn PDF document text
    • https://lightsourceindiana.com/wp-content/plugins/super-forms/uploads/php/files/9b9ba7af2c74646594c1f43d8b074281/giwidomeretapatuposunup.pdfIn PDF document text
    • https://fruzsiflame.hu/userfiles/file/92626403410.pdfIn PDF document text
    • http://csc0532.com/userfiles/file/20210620093726_txt89j.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160980417415a6---tafezujabozupunen.pdfIn PDF document text
    • http://31kouqiang.com/userfiles/file/1625883716.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/74407133921.pdfIn PDF document text
    • http://lotusromeo.fr/app/webroot/files/userfiles/files/toberazigupox.pdfIn PDF document text
    • http://www.ecostroyservis.ru/File/95298519161.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16114296c7c682---93169670581.pdfIn PDF document text
    • http://shangrilatheshow.com/ckfinder/userfiles/files/ninegosamoxapewovutalola.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/16094578da1cfa---wiramidevivikedisivezob.pdfIn PDF document text
    • http://nct-vn.com/userfiles/file/jufeletaj.pdfIn PDF document text
    • http://bsp-oblspl.org/ckfinder/userfiles/files/24043244460.pdfIn PDF document text
    • http://intersonik.eu/upload/files/retefowasusiwof.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077cb9ccbe03---31235224815.pdfIn PDF document text
    • http://rabotatver.ru/userfiles/admin/7805465604.pdfIn PDF document text
    • http://peterpan1996.it/userfiles/files/zakexiwederid.pdfIn PDF document text
    • http://amandatravel.com/userfiles/file/xobigiregopurukixeji.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=my+friend+pedro+play+onlinePDF 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_off0000e550.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE550 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD67 10332 bytes
SHA-256: 68a8fe9008e1deda6ebbe8c00fd7314e57dd89e723e5dc7a9a51e3f86175a984
font_02_sfnt_off000114be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114BE 18016 bytes
SHA-256: 3a92c6fd7ee3786a752aea0c31e3d405fb4b466f1c51c792afc29fcf3a383cb9