Malicious PDF — malware analysis report

Static analysis result for SHA-256 346e3d42cff0720c…

MALICIOUS

PDF

72.9 KB Created: 2021-09-25 15:59:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8d41e641670432a8917dec5dcc44af4d SHA-1: 951678957e0d24222bdc93f1e7cff8b8e4171e95 SHA-256: 346e3d42cff0720c39670540526901ae2a33e58db70cd0d695159f8eb35ccd37
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as containing numerous links to potentially malicious websites, including those hosted on compromised CMS platforms and disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the embedded URLs and link farm structure suggest an attempt to redirect users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9940

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://coretry.ru/uplcv?utm_term=what+is+koplayer
    • http://skyrybupaslaugos.lt/uploads/files/40943800368.pdf
    • http://hieuchuan.com/upload/files/25213538481.pdf
    • https://alrukn.co/userfiles/files/motidid.pdf
    • http://sinoscaform.com/upload/ckimg/files/202109161052455210.pdf
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/16143a372454df---didog.pdf
    • http://xtra360.net/campannas/file/3737902067.pdf
    • https://matrainagycsalados.hu/userfiles/file/65911068487.pdf
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/sudiraxuxupofogakivawum.pdf
    • http://stavo-bazar.cz/userfiles/file/dufixijurifo.pdf
    • http://soeurs-scjboran.fr/soeurs/upload/files/5602041911.pdf
    • http://ck-kutnahora.cz/gais/image/file/30424637627.pdf
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bbc6a82f13---wosumebikalora.pdf
    • http://contactfm.be/userfiles/files/19693007277.pdf
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/16147c8bec652f---bazegupovuka.pdf
    • http://videoacceso.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136e80841dbf---32259483334.pdf
    • https://razredna-nastava.net/files/96763004927.pdf
    • https://maurinet.com/userfiles/file/83722276336.pdf
    • http://chipmax.in/chipmax/ckfinder/userfiles/files/39011334265.pdf
    • https://vaitinhdien.com/app/webroot/upload/files/mukotitotanabikod.pdf
    • http://onsijsselstein.nl/userfiles/files/ranilofiwaluw.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/4acq9c6usjud4an69u1f9jjou2/66125697786.pdf
    • https://wroclaw-effatha.pl/grafiki/file/felagupujusorive.pdf
    • http://www.texaco.bargiel.com.pl/ckfinder/userfiles/files/firagaka.pdf
    • http://german-ex.com/images/blog/file/16127249543.pdf
    • http://msslink.ru/userfiles/files/385661758.pdf
    • http://dichvubaove.online/upload/files/muzemudekep.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_off0000ba41.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBA41 16792 bytes
font_01_sfnt_off0000d253.bin
8b6f02f8f85b95aedb2784c1b4747ae722c5638d9e8c83ec2daece46e10fdba0
pdf-font-stream PDF embedded font (sfnt) at offset 0xD253 16776 bytes
font_02_sfnt_off0000fd7f.bin
d9f40db9db09672f5bd8514b3b8308e04da11f1395fd91acfb8f4c6c8d0f8729
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD7F 10444 bytes