Malicious PDF — malware analysis report

Static analysis result for SHA-256 a858a25532807091…

MALICIOUS

PDF

85.2 KB Created: 2021-09-13 08:59:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 23138636c936024ad216696bd7f7d342 SHA-1: d325bd2d29d40d76c203dadce21e3ce1018a5c0b SHA-256: a858a255328070919372ac10c8cb4f041eb5b88385d4031bd26fb747cacb78fa
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, including links to compromised WordPress upload storage and disposable hosting, suggesting a phishing or redirection attempt. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lead users to malicious sites or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • 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 http://businessdevelopmentcenter.pl/uploads/userfiles/files/45644001783.pdf In PDF document text
    • https://buddhaart.in/userfiles/file/1245114375.pdfIn PDF document text
    • http://wuxihemei.com/ckfinder/userfiles/files/20210910_222108.pdfIn PDF document text
    • http://aliguoriarchitetto.eu/userfiles/files/debivatetaganod.pdfIn PDF document text
    • https://istanbulbalbir.com/upload/ckfinder/files/20217785401.pdfIn PDF document text
    • http://selfmadefilms.nl/userfiles/files/10964948281.pdfIn PDF document text
    • https://shoppingplanet.ro/ckfinder/userfiles/files/85119967172.pdfIn PDF document text
    • http://digilit.ir/basefile/digilitir/files/9507942872.pdfIn PDF document text
    • https://pharma-tools.pl/galeria/file/muzekikakiludegefidi.pdfIn PDF document text
    • https://altinhediyeler.com/calisma2/files/uploads/6790182120.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bf6c727da5---25963519106.pdfIn PDF document text
    • https://sharenkon.com/files/kevilatapadejijo.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613334a30aabe---47720550411.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612eb8c3555cd---788053289.pdfIn PDF document text
    • https://sanmuabancongty.vn/images/content/files/28228207576.pdfIn PDF document text
    • http://eminenceinc.com/userfiles/file/wixinonuladefax.pdfIn PDF document text
    • http://dentherapia.hu/files/file/42326952716.pdfIn PDF document text
    • https://tahubunting1.com/contents/files/34546754155.pdfIn PDF document text
    • https://irrisyst.eu/files/file/82233945210.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/16138ba26863fc---30143384304.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161301ca5d2aa4---nezesiwosekubuze.pdfIn PDF document text
    • https://lawtutors.co.uk/js/ckfinder/userfiles/files/bijepivasibox.pdfIn PDF document text
    • http://margheritango.it/userfiles/file/pubebe.pdfIn PDF document text
    • http://www.iuoelocal870.com/kaizen/ckfinder/userfiles/files/lupujomusibuvokavuzugewi.pdfIn PDF document text
    • http://csc-021.com/userfiles/file/20210901112518_zlkjrg.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=how+to+convert+audio+to+mp3+on+android+phonePDF 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_off0000e1d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1D1 19912 bytes
SHA-256: 923408515d388ff08ae37a82e746fc975b69a3e865217426014e42323f893034
font_01_sfnt_off00011573.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11573 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012d8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D8A 10980 bytes
SHA-256: 30524f25999a90c88e6ff76e8c48f31c061989a6dd5b6a6330d209f32c519c94