Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ff939043b54a956…

MALICIOUS

PDF

84.8 KB Created: 2021-09-01 09:50:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-07
MD5: 187a72c2604b0380bdd5fe35f44fbb18 SHA-1: a645c79a00b5427fab615dd969f0315389330e88 SHA-256: 3ff939043b54a9563a4edc7a65924fd4b177f1c1624b81e0edf22a32596a9822
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous external URLs, many of which are hosted on compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple links on disposable or compromised hosting suggests an attempt to obscure the ultimate destination and evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f626552b66---talosumuvibo.pdf In PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607690c427e5e---78617386745.pdfIn PDF document text
    • https://bruceleevideos.org/images/file/1991559090.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/160805fb0dde48---16509589136.pdfIn PDF document text
    • http://skncn.com/u/files/91346312014.pdfIn PDF document text
    • https://khotelmarket.com/FileData/ckfinder/files/20210810_80E3E4D575182D87.pdfIn PDF document text
    • https://propactionvehiclesuk.tv/userfiles/files/27795676799.pdfIn PDF document text
    • http://architetturaurbanistica.it/userfiles/files/38126622895.pdfIn PDF document text
    • http://dbcasagayathottam.org/assets/uploads/cms_images/files/33716072749.pdfIn PDF document text
    • https://habibitours.net/ckfinder/userfiles/files/xadopekowugakivozema.pdfIn PDF document text
    • https://ghnservizi.com/file/11811073631.pdfIn PDF document text
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/d5a618f510ece0582e7d82c960f4c2d0/xiwaxajowif.pdfIn PDF document text
    • http://andrewsexes.org/clients/867461/File/kurotovizaxu.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a1ec8adcc75---gapituw.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/160846f93b238f---gubujevokajekewobubebifod.pdfIn PDF document text
    • http://www.sphotobooth.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070ce9e30a96---75503760784.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/4b093241c95e759ce90a31ecf83abce3/47055486296.pdfIn PDF document text
    • http://sgyscom.com/upload_fck/file/2021-7-17/20210717154135510831.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/tdvomfqui0v1lauk66kfq9t3nq/jimep.pdfIn PDF document text
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/0fba431a1d0229755faa260115162412/98720706293.pdfIn PDF document text
    • http://phantasos.org/userfiles/file/bogesuremupunamewowa.pdfIn PDF document text
    • https://greyquotient.com/wp-content/plugins/super-forms/uploads/php/files/b6ce4ac1ac47165d8c37586c8602d0bb/24743774756.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=appraisal+system+in+hrmPDF link annotation
    • https://www.posluh.hr/ckfinder/userfiles/files/7253851531.pdfIn PDF document text
    • 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_off0000e4d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4D2 19024 bytes
SHA-256: c88da2430387aa165d5d2f2f7f4d4ca67cd8393613c2e7308d167557a25f3e28
font_01_sfnt_off000115da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012df1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DF1 10492 bytes
SHA-256: f824bec7f6bc2e0d0570b0a3999ed3c942c79768cc38e4d90678cb8d27f44b93