Malicious PDF — malware analysis report

Static analysis result for SHA-256 0fb8953889994392…

MALICIOUS

PDF

83.1 KB Created: 2021-08-17 12:17:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 05ecb3a5f9aac30e2e60549e86df6269 SHA-1: 92a77cb56d43b9983a24f1004bf8de0232379c78 SHA-256: 0fb89538899943923f2d6b7f4c6074b69e0b67e739c0aba7fe4f04eaff7a9efb
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO poisoning to distribute further malware. The embedded JavaScript may be used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://pistant.ru/uplcv?utm_term=exercices+sur+notion+de+fonction+3%C3%A8me PDF link annotation
    • http://xn--o79av69abka850ab6c.com/upload/file/202107090750163432.pdfIn PDF document text
    • http://gocep.org/data/userfiles/files/20288332512.pdfIn PDF document text
    • http://nexxosrealty.com/userfiles/files/51677054087.pdfIn PDF document text
    • https://www.alapan.org/fckimages/file/99273308492.pdfIn PDF document text
    • https://dubigroup.com/admin/fckeditor/editor/filemanager/connectors/upload/file/96700772966.pdfIn PDF document text
    • http://cerescommoditiesltd.com/Images_upload/files/xememo.pdfIn PDF document text
    • https://theurbanthinktank.com/files/lunavikirosonikazudufij.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/cpfhfkroatku9uaarglvt2fgd0/kuwuberarevurimosaxijodol.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160d035d01a14a---85829077601.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb9575d969b---refebe.pdfIn PDF document text
    • https://reaga.net/js/ckfinder/userfiles/files/55294649184.pdfIn PDF document text
    • http://ewtch.com/upload/files/kipojowewinewogibosus.pdfIn PDF document text
    • https://xn--22ck6bdp5cach0mc23a.com/ckfinder/userfiles/files/mapanidagevupi.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/7a26c120c4ecd6db8631f690d95964f1/58306195066.pdfIn PDF document text
    • https://armenia4d.com/contents/files/67068321747.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3d1915c7b3---juxomokevuze.pdfIn PDF document text
    • https://inprovit.com/ckfinder/userfiles/files/xivajelotolixikamusojas.pdfIn PDF document text
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/160f47fba1597f---ruzedelikoriv.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/5db2740f9f745ba35f1399a99c45f869/90197187077.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16076aeb1f2445---62704825755.pdfIn PDF document text
    • http://jinyudachem.com/upload/files/65961036804.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607531bf35a4e---zubipewajuzodeb.pdfIn PDF document text
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/hvcqfpg9pieh33to6ge93eik53/dozududewawinimod.pdfIn PDF document text
    • https://jnvhardoi.org/ckfinder/userfiles/files/womokomajizaxip.pdfIn PDF document text
    • http://prttour.ca/FileData/ckfinder/files/20210607_63C338A0CADFA01C.pdfIn PDF document text
    • 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_off0000d85c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD85C 19676 bytes
SHA-256: f84859bec3017a92eb313602d41706c8f3d1f7c71c02257b6f1edf320fdedb7e
font_01_sfnt_off00010a5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A5C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012273.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12273 10944 bytes
SHA-256: 8b422b10d8e685705b2a050c7af4dd120fc86ed20069cf8a8aea7f7764c9e01c