Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a52469f0cecced4…

MALICIOUS

PDF

79.8 KB Created: 2021-09-19 14:50:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5f34d5d7ec2645b7ed6acda28586cf5b SHA-1: 9f6eb94dce7d6f5861c6b745c8e9f2c942c59459 SHA-256: 4a52469f0cecced497a8f81ad8fc67e747628f86dc02fdcf0669d58aa5378e74
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable domains and are structured as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of a link farm suggests an attempt to obscure the final destination and evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://halkum.rs/files/lezulivilovudeb.pdf In PDF document text
    • http://bolt.fo/public_html/userfiles/files/minoluduselemowo.pdfIn PDF document text
    • http://gramercygrand.ru/files/file/69014942253.pdfIn PDF document text
    • http://iwilldoit.ru/uploads/files/files/13496098777.pdfIn PDF document text
    • https://anitacalderon.com/ckfinder/userfiles/files/vumepinofodobobakaxumij.pdfIn PDF document text
    • http://bwemfjhjk.friend-match.com/upload/files/sidavufar.pdfIn PDF document text
    • http://ymmicro.com/files/files/pomiwupafojuzor.pdfIn PDF document text
    • http://aimecostruzioni.it/userfiles/files/rokazijusom.pdfIn PDF document text
    • https://ksi-system.pl/editorfiles/file/88303989036.pdfIn PDF document text
    • http://evevoyance.fr/adh/.-/file/63060994596.pdfIn PDF document text
    • http://hublihorse.com/uploads/userfiles/files/sidulo.pdfIn PDF document text
    • http://kfgame.snailgame.ru/upload/files/20210914080208.pdfIn PDF document text
    • https://osakaav.com/userfiles/files/telutipafonutopin.pdfIn PDF document text
    • http://hijoin.hu/editor_up/monepusodosago.pdfIn PDF document text
    • https://www.adoz.cz/ckfinder/userfiles/files/vimenomugiboba.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614137c889e6e---42412137552.pdfIn PDF document text
    • https://pannonfinanz.eu/editor_up/sarutaxiwubuzuranozepa.pdfIn PDF document text
    • http://cuuhoatudong.com/upload/files/zonulikawugijivaf.pdfIn PDF document text
    • http://sity-luxe.ru/userfiles/file/83239808405.pdfIn PDF document text
    • https://binarbaidfabrication.com/public_html/userfiles/file/25519488788.pdfIn PDF document text
    • http://www.flamanville-76.fr/upload/file/ridavababilafukel.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/9v2imvch53g1ba92aaftqdbde6/7021874430.pdfIn PDF document text
    • https://360clothing.indicsys.com/home/www360cl/public_html/uploads/images/files/lukezuzurozikefufi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=best+android+stopwatch+appPDF 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_off0000d28a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD28A 17964 bytes
SHA-256: 25ad20839de19cc6fb4d2fada975a403623289d7a7b257739a6773f33b55e87f
font_01_sfnt_off000100e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000118fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118FB 10704 bytes
SHA-256: 48c86ecd0115bcae3943d4424a5ba1be682aaf3bc153cb2df12e33806d3e8334