Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1e506f58795a6b3…

MALICIOUS

PDF

81.7 KB Created: 2021-09-20 08:37:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 87ca41ecc5eb1c1da2cb464cc6e44a0b SHA-1: 33fe2be11e258474d634cc7c4710dd107f70d2f1 SHA-256: f1e506f58795a6b355bf1d2ad0aaf9312d926f8551239e1c6520226513a0f218
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript and numerous external links, many of which point to disposable hosting or compromised CMS uploads, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://elfuklid.cz/foto/Image/file/xapoximeraguzagato.pdf
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/16140cd95e2938---54162664474.pdf
    • http://www.elstar.ru/uploads/files/buzegopene.pdf
    • https://badoza.net/userfiles/file/62796044166.pdf
    • http://dichvumucin.com/upload/ckupload/files/41161838448.pdf
    • http://hoangminhsaigon.vn/@dmin/js/ckfinder/userfiles/files/65044688718.pdf
    • https://e-tta.com/app/webroot/userfiles/files/rinopekojebexoxoguj.pdf
    • http://szigmetal.hu/editor_up/19409694537.pdf
    • http://hoaiduc.edu.vn/ckfinder/userfiles/files/28891418324.pdf
    • http://elitaliaweb.it/upload/file/dunidapigodukavunizek.pdf
    • http://chornakorn-packing.com/ckfinder/userfiles/files/85563331954.pdf
    • https://zenit-npk.ru/files/file/zakobosulinosunifovi.pdf
    • http://aliceinformaticasrl.com/user/pages/15475042443.pdf
    • http://harposwebdesign.nl/app/webroot/files/userfiles/files/jugowebururawadaxevoruse.pdf
    • http://kibunajcc.com/ckfinder/userfiles/files/muxafeje.pdf
    • https://santa.sg/images/users/00000000/files/vozufudadofonofuwid.pdf
    • https://agmatbaa.com/upload/files/40246607059.pdf
    • http://xn--80aaeiengkwpz6p.xn--p1ai/pub/file/vatak.pdf
    • https://yuanfuconstruction.com/ckfinder/upload/files/nowenosefajalaf.pdf
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dee7718ec0---rimitasotomato.pdf
    • http://dayuntang.com/assets/uploads/ckedit/files/20210901153756.pdf
    • http://maybomnuocdanang.com/uploads/image/files/95618254251.pdf
    • https://parisnordmedical.fr/docs/file/95041362385.pdf
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16143c02cd44b6---90901910419.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=top+graphic+mobile+games
    • 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_off0000da88.bin
82d903af374a7eeec01fde580936241cb1696d39e44dc72f54d4645cb686fb11
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA88 10724 bytes
font_01_sfnt_off0000f2ec.bin
7ebd88a5a6d379b99f80f4a7e5e84b15394acfdf025bd76896f0a563a6421424
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2EC 17436 bytes
font_02_sfnt_off0001204d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1204D 16792 bytes