Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdff4c10b354f050…

MALICIOUS

PDF

86.8 KB Created: 2021-07-04 21:00:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b9e13def3cdc4c5c7aabcea79c28c3a5 SHA-1: 618079590d84407f25995ec337a633dcb8ed5969 SHA-256: cdff4c10b354f0502f5aef9345ce25a1e878a511f75cb2349c3a1d3b63116775
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://laborke.ru/uplcv?utm_term=south+american+country+english+official+language
    • https://allmassage.net/upload/file/20210515033755.pdf
    • http://zulassungsservice4you.de/bilder/file/31665260031.pdf
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/160741fd5a13ec---wetuvuduzenoruduwaripo.pdf
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/21k5qaf8g8ee7dgi842kb1ah6p/kanepob.pdf
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/160725c5762585---69746728919.pdf
    • https://gbagencement.fr/uploads/file/58537243681.pdf
    • http://bulmarconsult.com/files/kititidokijativibuxib.pdf
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/v1khl2cklhmjdlch5f5t3s0fpa/zatagujewimigobalidifivum.pdf
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/19ab2bddde813a0dde9b4563b0a22077/wogepekirebuduf.pdf
    • https://gofropack.com/wp-content/plugins/super-forms/uploads/php/files/fe79eff8e5dd535642b6be9d38f40da6/govobolazijenasadamepe.pdf
    • https://cal.lighting/wp-content/plugins/super-forms/uploads/php/files/88c06a79fa1ae8b85fa04b7451d75a2f/18419768340.pdf
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160adfcae90808---xadozirubuli.pdf
    • https://lawina-radom.pl/files/file/93199482191.pdf
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/cb0526d882a3114bd9fc4171d553ccb2/84805717948.pdf
    • https://soba05.org/wp-content/plugins/super-forms/uploads/php/files/520ec791564f1f6eb2fc0d3e971c0bee/31055605623.pdf
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b5188fadbe2---53544364814.pdf
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/v7lm1aaf70rsjpbohn2prvjlku/tikopogugenelebawiz.pdf
    • http://studiorestagno.eu/userfiles/files/tilazogaduribulitol.pdf
    • http://newgrids.com/userfiles/file/90844288314.pdf
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/9d833e88dcf17dde5f55767bffc46293/45143300351.pdf
    • https://akproauto.com/nbloom/fckuploads/file/kobasikezurifodegemosex.pdf
    • https://bd-sokolovska.eu/userfiles/file/19137259287.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_off0000eef5.bin
2d30e8e01f68383606df42e5d682993beb8aa0307613ae72d3f7560ee9795288
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF5 11072 bytes
font_01_sfnt_off00010897.bin
e684d23dd9fad7234f8c097c32dab4e38c17d1d8ca0d0f836c950b81415b1144
pdf-font-stream PDF embedded font (sfnt) at offset 0x10897 17252 bytes
font_02_sfnt_off000135c5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x135C5 16792 bytes