Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff33ed78d765eb18…

MALICIOUS

PDF

79.9 KB Created: 2021-06-30 21:19:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 53f65c15f358ec75c0ebca395e2fa8e4 SHA-1: 5f7d1f611dadece5c042a60549edbc89f862b0a6 SHA-256: ff33ed78d765eb18efcb2408f813a0ad4751f439232bc3fe2956175ef209b295
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised WordPress upload storage, suggesting a phishing or malware distribution attempt. The document body was unreadable, but the presence of numerous links to potentially compromised sites indicates a malicious intent to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083412f73781---20069267962.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2b2c41d0d9---mebadujakogalogakibore.pdf
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f0c0875a9b---47915885121.pdf
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160712f010679b---kojivivakudurigejux.pdf
    • https://ethiquedevelopers.com/wp-content/plugins/super-forms/uploads/php/files/8f5c2611c9aeacf8ec7d3f49410888af/jalijoliwuvepug.pdf
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/353a50ffb400b6863023de05f1f7993b/kenupedivegaw.pdf
    • http://martonaroniskola.net/userfiles/file/kupajopinuwikerutixolu.pdf
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/b54b7437d2b486e2785a875afbb86355/54636384121.pdf
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8c7b16714---vebimiriwoxopanan.pdf
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/l641shcefavhaqv6qop764v7e4/99246860064.pdf
    • https://bibliotheque-des-arts.ch/ckfinder/userfiles/files/9188489966.pdf
    • http://eksan-ltd.com/userfiles/file/25264483586.pdf
    • https://ksboutlet.com/file/files/wewogupawotadubamajepaw.pdf
    • https://samsungdvmklima.com/upload/ckfinder/files/betekobug.pdf
    • http://songiadabinhphuoc.com/upload/ck/files/bolibivotuni.pdf
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/57d7f082d53f51c5d55af844adbb4a92/18694497082.pdf
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/72f98c6047caf304fade0f665cf39f3d/wigusaxewurunabazin.pdf
    • http://hoondb.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084fb15659a0---66246188062.pdf
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/adec402d1ffa46bf0ec78d3c76a4b1b3/83466248770.pdf
    • https://anctools.com/ckfinder/userfiles/files/xonepejimapekojuwakel.pdf
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/1608d332ba025c---pefibopapitojasuzoxajakuv.pdf
    • http://doubles301.jp/files/ckeditor/files/81559579223.pdf
    • http://bonapartefamilynetwork.com/clients/7/7d/7d081654635712149502d88e72c54c2d/File/logumetekobogegusa.pdf
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/755fba852398099d89e718e9d2b4ecdb/wamabiveni.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=water+vascular+system
    • 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_off0000d7fd.bin
c69005b7bb131abdbf1d225161358c86adec7cccdf77be0505f080ed0a957088
pdf-font-stream PDF embedded font (sfnt) at offset 0xD7FD 10348 bytes
font_01_sfnt_off0000ef7a.bin
74e10ff80d47be1b8900dbf2c38b77db42b8ee8cc2b870501c5b292c76e36680
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF7A 16468 bytes
font_02_sfnt_off00011a4c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A4C 16792 bytes