Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1c49a6405f7114f…

MALICIOUS

PDF

93.0 KB Created: 2021-09-18 11:49:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0fc8139f467e27c87e782d101a3c8d9d SHA-1: 58f456628dbd1e4f7d6afd537e0269c2e8e45ea2 SHA-256: a1c49a6405f7114ffa2717c2478d3b45b677b8d7443abe439d8cdc97604408d6
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised or disposable hosting. Heuristics indicate a link farm designed to redirect users, and ClamAV detection confirms its malicious nature. The embedded JavaScript likely facilitates the redirection or exploits a vulnerability to execute a payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://kingsap.com/file_media/file_image/file/mujedaroloxunivu.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131db0a694c6---gagofakegasijafolu.pdf
    • https://ebal.ro/app/webroot/files/userfiles/files/59292847294.pdf
    • https://www.asoriofrio.org/ckfinder/userfiles/files/vedizadexikofuvunaxaf.pdf
    • http://postelezmasivu-brno.com/ckfinder/userfiles/files/77847125884.pdf
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140047e30233---7971417483.pdf
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1614141f5844fe---66745367307.pdf
    • https://etonbio.com/newsLetters/images/file/99607151209.pdf
    • https://zevkotodoseme.com/upload/ckfinder/files/65058718356.pdf
    • http://asea-admin.com/_userfiles/file/20210906045354.pdf
    • http://pomodorolennep.de/gfx/userfiles/files/nupogotuxid.pdf
    • http://frigotechreina.com/userfiles/files/zitidenoravemobuvemofis.pdf
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/eb2e6af967d618acb0606bf7ed39bb65/24867159022.pdf
    • http://giaodantanthaison.com/Images_upload/files/kabiforodoxubejowewu.pdf
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/5a92bcb44b95ce7b6650267afa24b3ad/90575785118.pdf
    • https://haciendaloscipreses.cl/upload/file/pifeg.pdf
    • https://rafaellopezehijo.com/upload/files/11994945707.pdf
    • http://sjmhospital.org/files/js/ckfinder/userfiles/files/bunijoxunedilitokon.pdf
    • http://sirinthepgroup.com/userfiles/file/zurelamijimawa.pdf
    • https://piti.leaddeehub.com/userfiles/files/xiwevuboverotom.pdf
    • https://shinko-tw.com/UserFiles/file/7233357976.pdf
    • https://indiachristian.org/uploads/files/13767684390.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=golf+swing+apps+android
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fbcf.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFBCF 16792 bytes
font_01_sfnt_off000113e1.bin
33cee668110d8bd22d6198f46a857cea1fd1273d420fe521640c4369b3b061cb
pdf-font-stream PDF embedded font (sfnt) at offset 0x113E1 22312 bytes
font_02_sfnt_off00014ee6.bin
73738a7bd5a2893c8428863223c97345b7a93c958fb2bad4a2ff319d0c3c9474
pdf-font-stream PDF embedded font (sfnt) at offset 0x14EE6 10568 bytes