Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c1f59afd577a8ac…

MALICIOUS

PDF

85.1 KB Created: 2021-09-08 17:28:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d4f3e3f88953587fa15f32d1ca9cdb6c SHA-1: 7c2c6dc7e00699508d5383bcd1080a4a54186173 SHA-256: 6c1f59afd577a8ac550d9c91fb3e3ead9760c5e24faf3117ab59b193bfc75085
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links, many pointing to compromised or disposable hosting, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution via these links. The presence of multiple external URI heuristics further supports the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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.
  • 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://noventa.cz/media/files/file/virisutuwunobuzapi.pdf
    • http://sosonomo.com/ckfinder/userfiles/files/73160643203.pdf
    • https://markyatirim.com/resimler/files/wovove.pdf
    • http://maychaybocaocap.com/app/webroot/uploads/files/88882881133.pdf
    • http://www.sport-konyv.hu/userfiles/file/jemufijuwukovodokalago.pdf
    • http://spbmedaks.ru/sites/default/files/uploads/gaxuvofegimuditejuxi.pdf
    • http://honeycontacts.com/uploades/userfiles/file/sevebu.pdf
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/c8b33iri572lu0gsnvf4p5lim3/nadopomujabakefebenipevit.pdf
    • https://fminterativa.net/cms/plugins/ckfinder/userfiles/files/kolibo.pdf
    • https://solturism.ro/images/file/50925043296.pdf
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161303eee05205---rogijafilopevasowa.pdf
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/22cea8e8408a4fe9719b6135bf8c7f39/jumolarezosasadaz.pdf
    • https://er-cardiff.com/eurostyl/photos/file/nusotuxabiwik.pdf
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/9f37dofigpk67q84u4muru75c7/juruzuferip.pdf
    • http://soldearenales.com/galeria/files/laxanivuz.pdf
    • http://pphjako.pl/userfiles/file/356342713.pdf
    • https://honghow.com/ckfinder/userfiles/files/24607706366.pdf
    • http://semihkerpiccilervesupersound.com/upload/file/potenudanukoxakex.pdf
    • https://mami-m.com/Uploads/userfiles/files/liluxedekawupemenisuniwos.pdf
    • http://gardens-spa.com/user_pict/file/guwekuzazovumunize.pdf
    • http://nyitotthaz.hu/userfiles/files/jikib.pdf
    • http://colorfulmedia.de/fotki/fotki/file/52540043185.pdf
    • http://www.anapharmata.hu/ckfinder/core/connector/php/files/giroxopomeguzokun.pdf
    • https://spa-salon.ru/ckfinder/userfiles/files/puluxeza.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=exercices+cryptographie+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_off0000e172.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE172 16792 bytes
font_01_sfnt_off0000f989.bin
fadf7086894806d4659f497c377b728c817cb0d7c5de836363a298982b965b19
pdf-font-stream PDF embedded font (sfnt) at offset 0xF989 10948 bytes
font_02_sfnt_off000112e7.bin
b2fe4b7b95ed789ad74524031deab93090a403f168da78d2317a53ebeb16175f
pdf-font-stream PDF embedded font (sfnt) at offset 0x112E7 19740 bytes