Malicious PDF — malware analysis report

Static analysis result for SHA-256 3dcec386f81bff57…

MALICIOUS

PDF

86.9 KB Created: 2021-06-28 09:41:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 56cb6d9945f9184a200978f8ab804f69 SHA-1: 1b1c2d5e6ed0b43ba17c1253e1575697a2e91f5f SHA-256: 3dcec386f81bff57d57f17da82c34c77b3c29674603d5f0912c7a061b598230a
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics reveal it functions as a link farm, with many URLs pointing to compromised CMS upload directories or disposable hosting. This suggests the document is designed to lure users to malicious sites, likely for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://mu-rrrc.com/userfiles/file/zuviguwuda.pdf In PDF document text
    • http://honda-vo.com/upload/file/50706456185.pdfIn PDF document text
    • http://maynenkhiinverter.com/media/ftp/file/27168587378.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/616426b909be9a24650cd43c0f376338/damuzasazasoroziruvi.pdfIn PDF document text
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/c389a413954f58f1ee4a492db3eb08b6/73087473266.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/16073a92f45c63---gifutevilaxizen.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c6cf9a157b---70742787586.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072368bb172e---misexuzoveg.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c3a703aa00---55037489606.pdfIn PDF document text
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/c8c495f0af2accbaa4cbc6c153721b8d/64647260175.pdfIn PDF document text
    • http://perfekttorun.pl/pliki/nitisepaxosixexijimofevab.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfaa91cf013---38313679713.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cee73e42e27---23425493279.pdfIn PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607427e93d170---85554750539.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/e4hdh4nkh9uo1jf1abiq43itd2/tonubarizame.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/ss34q84roe7sse0g782id02sos/29435582242.pdfIn PDF document text
    • https://www.wflorlando.com/wp-content/plugins/super-forms/uploads/php/files/70e2b4afae00a2d83849abd01d519d3f/36534032957.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607617eedd1f9---97847992306.pdfIn PDF document text
    • http://czpohledavky.cz/userfiles/files/29062333202.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607ea6a12740d---39713020318.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c880d6a25a3---malotarogukifidit.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/d5a098e326ffb6e2da462e245232c216/mimigamijurisafu.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/rexoxufi.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b75cc2e94ac---bukunojukixa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=watch+fast+and+furious+9+free+onlinePDF 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_off0000ed6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED6F 18364 bytes
SHA-256: dabec89c6e97b04dad3224ba5346a6163b4b7320f4008941231a8e3583fb4d87
font_01_sfnt_off00011cfe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CFE 10836 bytes
SHA-256: 1f42c090e6fe684c8d743153142c89ce1cbef333c4707e98992c60668c3cfc1d
font_02_sfnt_off00013606.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13606 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1