Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bd03c535ebb1928…

MALICIOUS

PDF

76.0 KB Created: 2021-10-04 05:58:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 513625a2ea8c027a7b6f4f1dd0007c53 SHA-1: 765e918e62befe2b565ed57e2348fdd15c078df4 SHA-256: 8bd03c535ebb19282c4128f226e393ae07ff4eccb1c3feb1a05a9a6d012535d8
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous URLs, many of which point to compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document is structured as a link farm on potentially untrustworthy domains. The embedded JavaScript likely facilitates the redirection to these malicious sites, contributing to a phishing or malware distribution attack. ClamAV detection further confirms its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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
  • 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.
  • 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.
  • 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://neonatal-surgery.ru/userfiles/files/22412308097.pdf
    • https://madhubanindiancuisine.com/nbloom/fckuploads/file/pumudo.pdf
    • http://demo-jesma.shopcloud.es/ckfinder/userfiles/files/jepimiluzo.pdf
    • http://goldsunjsc.com/upload/files/jawerinexebolapim.pdf
    • https://agronlogistics.com/userfiles/files/91774066641.pdf
    • http://businessvaluationapp.com/fck_files/file/pubufopu.pdf
    • https://bio-obst-und-gemuese.de/userfiles/file/bimixabasavumapeb.pdf
    • http://christopherspubandgrille.com/userfiles/files/99792638787.pdf
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/16155a3e050ddb---danowimimuku.pdf
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/161464bcb7c400---bunujaxulitutaxuke.pdf
    • https://barcelonacentromedico.es/files/galeria/files/35737669119.pdf
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/856bc216c79eb95d163a9f19b1c45520/66946480789.pdf
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/0dc011a55e267808ee4c0a649200ed05/pigebatuxazeginogis.pdf
    • http://gshosnab.ru/userfiles/file/6940899002.pdf
    • http://wuyioutdoor.com/userfiles/file/lodajamunojiviravosunij.pdf
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/ovhd1974un1bajc66ro49blsg1/ruzojufibirinaxuzores.pdf
    • https://molecult.metallo-tests.ch/sites/web/upload/files/31562376817.pdf
    • http://brenno-tojestto.pl/userfiles/file/wedosiximifip.pdf
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/161357650d5b66---jebuwuxapikezidu.pdf
    • http://wolfpackbasketballacademy.com/content_docs/32771025764.pdf
    • https://moveo-sport.pl/userfiles/file/guvoxunogijivafifofoti.pdf
    • http://rama-sp.com/rama/webroot/js/ckfinder/userfiles/files/88178174316.pdf
    • http://gradn.ru/uploades/fckeditorfile/nifojojularujulosikigase.pdf
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/e356ade378efe1fc6581f661b40b8004/57105340455.pdf
    • http://vijyaiprismcrm.com/userfiles/files/47656427589.pdf
    • http://cjmfgxfollow.morefriendship.com/upload/files/xidomepulumufutezigap.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=find+the+derivative+of+tan+x+from+first+principle
    • 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_off0000bccd.bin
8a4dfc119bf55415268532ff3485cd70d3e0cb606dde54bbbc495794936dd8b6
pdf-font-stream PDF embedded font (sfnt) at offset 0xBCCD 20068 bytes
font_01_sfnt_off0000f08b.bin
e919f16fb2fa5a5c9c3869c9811ef1f13d587b5788c3a96c5aef0345f46000d3
pdf-font-stream PDF embedded font (sfnt) at offset 0xF08B 11032 bytes
font_02_sfnt_off00010a06.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A06 16792 bytes