Malicious PDF — malware analysis report

Static analysis result for SHA-256 fbf3b2ea4bebf6da…

MALICIOUS

PDF

75.3 KB Created: 2021-07-15 10:37:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b917539230e6925a54cbc8475758bdac SHA-1: 437aab3045db42bdd2ab6962ff73247152b2d833 SHA-256: fbf3b2ea4bebf6dac8e3bd014307686488e6fe1d83be3ee52630dccc811007c7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The presence of embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic further support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://medvor.ru/uplcv?utm_term=can+obdii+manual
    • https://songhong.info/userfiles/file/raveku.pdf
    • https://sarujiovalente.com/wp-content/plugins/super-forms/uploads/php/files/blo3k6pft5pr2shv515nlp640n/nebedapanamosudarubobusat.pdf
    • https://aspirans.com/files/file/wexalumo.pdf
    • https://eyetracking.pl/userfiles/file/dekesonejoxapiw.pdf
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/2845162874.pdf
    • http://appli-veolia.net/ckfinder/userfiles/files/23295732300.pdf
    • http://helderlive.nl/ckfinder/userfiles/files/xoxobazovunadagusuruwam.pdf
    • http://ettorebelfioreliutaio.it/userfiles/files/mamiwijuzejagozo.pdf
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/160985a1c0f9d9---4699851318.pdf
    • http://airconbank.com/upload/fckeditor/file/54397112072.pdf
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16074c1657aaa0---jowudenitijijonegexu.pdf
    • http://traiteur-ribot.fr/userfiles/file/goxelidozujukufefa.pdf
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/54048334b2c706bc15dd22fd9633cff7/14648937579.pdf
    • https://otartufo.com/ckfinder/tartufofiles/files/64544051559.pdf
    • http://mindentudor.hu/userfiles/file/nonebew.pdf
    • http://aaaexpressac.com/userfiles/file/zigetezevuzovek.pdf
    • http://doks-films.com/pcms/content/file/86365605055.pdf
    • https://asset-books.com/userfiles/file/60318936240.pdf
    • https://www.helmmsp.ca/wp-content/plugins/super-forms/uploads/php/files/3dc0bbcf952e5bf7b4ee439163628f5c/vadugebebobukimegono.pdf
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc80c108ef---26138803406.pdf
    • https://mt-creativestudio.com/ckfinder/userfiles/files/57597527302.pdf
    • http://www.multigacos.com/admin/uploaded/fck/file/suzeluwokawew.pdf
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/a32c264bc2bd34a767bb9bf6b2c16661/lifelot.pdf
    • https://imagebeaute.fr/userfiles/file/misozekevaxedikuxipa.pdf
    • https://bluebeakbranding.com/wp-content/plugins/super-forms/uploads/php/files/2f4facfdbe76712dc3b64f1f77188a84/18031048612.pdf
    • https://yar-net.ru/userfiles/file/zixusezabufekorigixat.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c4a2.bin
043ad58a6babd240116ba783210d5821d55081e86b79da5fd27578e00961a020
pdf-font-stream PDF embedded font (sfnt) at offset 0xC4A2 16624 bytes
font_01_sfnt_off0000efd9.bin
0c721aa1900a376879b6f165a4ab4fc8441b6080b496dc6f2149662b5a4a8584
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD9 10184 bytes
font_02_sfnt_off00010689.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10689 16792 bytes