Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb2d40db08ecfe8e…

MALICIOUS

PDF

85.9 KB Created: 2021-09-07 01:26:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ad27bb2c687c565de438c0176d16b3cb SHA-1: f05f3479d40a30b267116e32cb79b98c91cc705e SHA-256: cb2d40db08ecfe8ed2b8bdfb8bfa82da28fc582809d7a18ec3bad28cacad87c3
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or other suspicious domains hosting additional PDF files. Heuristics indicate this is a link farm designed to distribute malicious content, likely for phishing or to download further malware. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://bechtoldpaving.com/wp-content/plugins/super-forms/uploads/php/files/e59ac010feba29b4e8b0d05afef8c661/maluj.pdf In PDF document text
    • http://5lovestartw.com/CKEdit/upload/files/nulafeg.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ccff445034---folepog.pdfIn PDF document text
    • http://nmglyxx.com/userfiles/file/kamuduborazanudamasak.pdfIn PDF document text
    • http://poultech.net/d/files/33222191366.pdfIn PDF document text
    • http://foodchemsino.com/d/files/gosudejoled.pdfIn PDF document text
    • http://debandhelder.nl/ckfinder/userfiles/files/76370065865.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/40b6bceacecdc915e486cc77f64b0ce9/jitusiwezafuweginuj.pdfIn PDF document text
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/iqoo1l4fruakc1b1j45qnll0o3/fotivugotox.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609224efc12bf---73025159283.pdfIn PDF document text
    • https://vidaleve.net/ckfinder/userfiles/files/pifulepogini.pdfIn PDF document text
    • http://hengtaixin.com/HangShun/ckfinder/userfiles/files/pujibefewaforiniwigimerin.pdfIn PDF document text
    • http://thegioicamdo.com/upload/files/80549972590.pdfIn PDF document text
    • http://bachova-terapia.sk/images/file/vemegupep.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/2af7675390e064f10a1696aee1901521/xonotibofogatifedativomo.pdfIn PDF document text
    • http://hortherbpublisher.com/files/upfiles/file/gujev.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/b8a98f80c915b99458c298d4e42bd3cc/1526003747.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d3e4fd6a927---20691859227.pdfIn PDF document text
    • https://lederstuhlshop.de/ckfinder/userfiles/files/76604280960.pdfIn PDF document text
    • https://fobh.net/userfiles/files/99532738287.pdfIn PDF document text
    • http://csc0351.com/userfiles/file/20210821191804_zo1wn0.pdfIn PDF document text
    • http://ballstonfamilymedicine.com/clients/861402/File/bipomonemexefu.pdfIn PDF document text
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/168tv95m64pbnt3aagn3elh020/zosefidikalolexodinadasa.pdfIn PDF document text
    • https://www.varisistanbul.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cda68c8052---banapamixepukedisurufi.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/16084e656bd85c---mimuta.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/ee5418052a54ff9e5ceda291d9ea9fa9/67344878605.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=organic+synthesis+pdf+downloadPDF 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_off0000e61e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE61E 18936 bytes
SHA-256: 0865e6a7e3f3b10adf073fc7d32139c332eb202a95f7d5a2e30176ce5b745d84
font_01_sfnt_off000117cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117CC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012fe3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FE3 11124 bytes
SHA-256: 1e99e0a70094a8376239243bb0993eb904b287722b30888c67857443f0b0d998