Malicious PDF — malware analysis report

Static analysis result for SHA-256 efd7117152c23d74…

MALICIOUS

PDF

71.6 KB Created: 2021-09-22 21:24:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 8e3f5973c8504336badfd9934f06df17 SHA-1: 7a3f951c18e874ec349decf2f61350e7703c2e0d SHA-256: efd7117152c23d745e81d3148fc47e03c653940d922b792249503c9a20aced57
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, pointing to numerous compromised WordPress uploads and disposable hosting sites, likely to distribute phishing content or malware. Although no scripts were directly extracted, the nature of the link farm suggests an attempt to lure users to malicious sites, aligning with spearphishing tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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://crysiq.ru/uplcv?utm_term=juegos+arcade+para+android PDF link annotation
    • https://www.hinkler.com.au/application/third_party/ckfinder/userfiles/files/nemiso.pdfIn PDF document text
    • http://autoachtercamper.nl/userfiles/file/21754360532.pdfIn PDF document text
    • https://eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/93938088386.pdfIn PDF document text
    • https://pellevah.com/upload/files/64437642444.pdfIn PDF document text
    • https://xn----8sbcehyodmtf1czh.xn--p1ai/userfiles/file/dadajerazexijonivupanu.pdfIn PDF document text
    • http://mdbim.pl/ubezpiecz/obrazy/file/53289631195.pdfIn PDF document text
    • https://techielingo.com/fck_uploads/files/89982152110.pdfIn PDF document text
    • http://muasamhangmy.com/ckfinder/userfiles/files/59307061430.pdfIn PDF document text
    • http://toyotacri.com/userfiles/files/fisulajubebeparikadipij.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/1612f05f55eb1f---74350686671.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613b80617fe77---tinubawiwi.pdfIn PDF document text
    • https://alajuusa.ee/media/contents/file/64470454840.pdfIn PDF document text
    • http://tentauto23.ru/ckfinder/userfiles/files/90595774606.pdfIn PDF document text
    • http://vititanon.com/user_img/files/xeliguxorimiwupatuxev.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/16130088adf720---29790040737.pdfIn PDF document text
    • https://shieldtech.cz/ckfinder/userfiles/files/taleferututapixom.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/827fcde55864ff29de2f71cb8f4c6a4a/72510468851.pdfIn PDF document text
    • https://sandp-engineering.com/ckfinder/userfiles/files/feluparogikabat.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140fe733614e---24564457903.pdfIn PDF document text
    • https://principesgs.com/userfiles/file/82245440521.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/iho6rhk6c3o7tngqjjh4htcbjn/tovenomekiwigidowek.pdfIn PDF document text
    • http://bladensburg.abwingsmd.com/uploads/files/zevibemukot.pdfIn PDF document text
    • http://websteravelandscaping.com/editorData/file/vorugepesixotuve.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f0de5eea01---43940416295.pdfIn PDF document text
    • https://abrasco.org.br/ckfinder/userfiles/files/xinopejuvarowupoxat.pdfIn PDF document text
    • https://hinodecoder.com/userfiles/file/nivogipifexes.pdfIn PDF document text
    • https://cytokin.ca/upload/editor/file/76989609827.pdfIn PDF document text
    • http://gilendor.cz/userfiles/file/sekeruvisitozadotafa.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_off0000b750.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB750 16316 bytes
SHA-256: 5c40259243db50b2632da74fb96ff61f119dc92cab4d1b1db9d85ebd306a0ea8
font_01_sfnt_off0000e072.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE072 10636 bytes
SHA-256: 4047d5636814b8e7b5b730735f6a22b0edcb32f9c8e722dc175eda88b8099df2
font_02_sfnt_off0000f8b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1