Malicious PDF — malware analysis report

Static analysis result for SHA-256 2a4c7599f258208b…

MALICIOUS

PDF

82.1 KB Created: 2021-09-14 01:30:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 68496af779244739a246a9a82a44f071 SHA-1: 43cf75b1a758c87e7b4d97638a1d6ab1dd160a74 SHA-256: 2a4c7599f258208b4b0ede12603ba371365faff9d1af49e01136b5c085f0d1c2
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, with one heuristic specifically identifying it as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to trick users into downloading a payload via the provided links. The presence of embedded JavaScript suggests it may be used to facilitate the download or exploit.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://gzafjc.com/uploadfile/files/fusonagerexumixeser.pdf In PDF document text
    • http://www.mananthavadynorbertines.org/www/js/ckfinder/userfiles/files/87619758724.pdfIn PDF document text
    • https://xn--80aggmy8c6c.net/UserFiles/File/batunelitudewotot.pdfIn PDF document text
    • https://worldpigment.com/image/upload/File/dalasabatowasetulok.pdfIn PDF document text
    • https://12shio3.com/contents/files/lovesebaxevolu.pdfIn PDF document text
    • https://adamant54.ru/userfiles/files/40205077306.pdfIn PDF document text
    • http://teusz.pl/UserFiles/file/xasekenupodij.pdfIn PDF document text
    • http://jiab.net/userData/board/file/fakiputusewanuvebedazev.pdfIn PDF document text
    • http://agro-vostok.ru/userfiles/file/5792429558.pdfIn PDF document text
    • https://autopits-directo.migrupoq.com/ckfinder/userfiles/files/jumiduxoti.pdfIn PDF document text
    • http://bradzo-ep.com/uploads/files/52344626232.pdfIn PDF document text
    • http://polimak.pl/userfiles/file/fusev.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161362f776979e---34130321874.pdfIn PDF document text
    • http://tipsclubcr.com/campannas/file/moguk.pdfIn PDF document text
    • http://clinicaveterinariacene.com/userfiles/files/dubixuliwenajazolaze.pdfIn PDF document text
    • http://hantechwelding.com/userfiles/file/2021091104163473499.pdfIn PDF document text
    • https://pasarantogel2.com/contents/files/papubawokavujuvivedeb.pdfIn PDF document text
    • https://bahia-group.com/ckfinder/userfiles/files/3966213521.pdfIn PDF document text
    • https://siliconautomation.com/userfiles/file/41012570973.pdfIn PDF document text
    • http://zatoodesign.com/userfiles/files/fedekisojanazaxe.pdfIn PDF document text
    • https://vsevolozhsk.mebel18.com/uploads/files/97195689202.pdfIn PDF document text
    • http://shengyaweb.com/uploadfile/file/2021091114004664.pdfIn PDF document text
    • https://patriciogaete.com/upload/file/vufuderafedumaradivudip.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=best+file+manager+apk+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_off0000d89e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD89E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f0b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0B0 18880 bytes
SHA-256: 885742f8df152238b63ac082c8f16f7033a7e631809e0b6606484ed72416d0db
font_02_sfnt_off0001218b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1218B 11072 bytes
SHA-256: 2cd50003d9d7884fdd0d013ca46ccce2c294b13af4ddf02d67831b6ab3233e45