Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5cc632b558cbc73…

MALICIOUS

PDF

86.0 KB Created: 2021-09-05 04:59:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6a0bc3d30e0b4a20610e094a5cc3ac3a SHA-1: 8ec2841865b648c0b4718c9ccd392ea52011941a SHA-256: c5cc632b558cbc73cb0b6c9c63a8090e2391492a43e99e9bdac9f490daec2cd2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs that point to compromised WordPress sites and other domains, likely serving as a distribution point for phishing or malware. The presence of external URIs and link farm heuristics strongly suggests a redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • 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://cructi.ru/uplcv?utm_term=value+investing+for+dummies+2nd+edition+pdf
    • https://www.ndgai.com/wp-content/plugins/super-forms/uploads/php/files/uilrumpa6qcfj7sb8445o2lmur/17863255057.pdf
    • https://travelstore.tn/userfiles/file/zekegaxedomosuru.pdf
    • http://paradisoseminatrici.it/userfiles/files/wemevizobimevazubinuwitab.pdf
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/ae088c49e957f21d74df49a26da1aeb7/72506670956.pdf
    • https://bestwaynepaltrek.com/ckfinder/userfiles/files/66981697011.pdf
    • https://nurea.se/currency/userfiles/file/84574585864.pdf
    • http://fu-xin.tw/uploads/files/202108260058313641.pdf
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/875aa5f187de8a2ba97ca09cadc34fcf/99579745363.pdf
    • http://suachuadienlanhhoaphat.com/hinhanh_fckeditor/file/wituxeruronezopikuxatelow.pdf
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7a2f34d5a0---29783405359.pdf
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d5d39883182---90819034830.pdf
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b30cf808b03---kilereketu.pdf
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609e62499ad50---jagiwugiweme.pdf
    • http://ucinnovation.ru/admin/ckfinder/userfiles/files/tovip.pdf
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/9721f187a6c0766eef7aedd8bcf79859/51632364544.pdf
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608155aff1c30---57278400077.pdf
    • https://conviviodihera.it/dati/upload/file/faluberaterogakatin.pdf
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb4d2284ddb---19153110232.pdf
    • http://ecohouse-lab.com/userfiles/file/zunop.pdf
    • http://birizgardenhotel.com/userfiles/file/82668524401.pdf
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c03be6dd562---xuxirupizuluwu.pdf
    • https://shared401k.com/wp-content/plugins/super-forms/uploads/php/files/e751e5f3943951e71d49016c7dbb4a55/gidovenomowix.pdf
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/n3el60n82sffvhvfpgt22um1qb/javigewijutirazixugapol.pdf
    • https://postelezmasivu-zlin.cz/ckfinder/userfiles/files/vuwitudebavupit.pdf
    • 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_off0000e99f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE99F 16792 bytes
font_01_sfnt_off000101b1.bin
0c6455c4d138b5b48a26c9642f3b9b53dd340e425168a682ef4c1dc04ef33680
pdf-font-stream PDF embedded font (sfnt) at offset 0x101B1 18100 bytes
font_02_sfnt_off00013082.bin
26e7653e9c0c38fb7f1d7f6b222ddde87fc50ba60bfd4a7ca8e075a0c6df84c4
pdf-font-stream PDF embedded font (sfnt) at offset 0x13082 11096 bytes