Malicious PDF — malware analysis report

Static analysis result for SHA-256 6665b140c4f70b79…

MALICIOUS

PDF

73.4 KB Created: 2021-09-15 17:49:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c356416b089a049075213a09dd48a028 SHA-1: 573cf41a10660b2d4a8fa9beb52028f1262b7a36 SHA-256: 6665b140c4f70b79be4f0db315b816bab1e24c5efe0fb1ef79f73d9161af4a5d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream, which is a common technique for delivering malicious payloads or redirecting users to phishing sites. The presence of a link farm pointing to compromised WordPress upload storage further supports a malicious intent, likely for phishing or malware distribution. The ClamAV detection and ML classifier also strongly indicate maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://image.dlib.vn/libedu/news/bachviet/20210909/file/40378334322.pdf
    • http://tanabuauto.com/js/upload/files/28625409979.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/bjnkcbiehadhimi6tfo1669snv/16571480519.pdf
    • https://www.abrasco.org.br/ckfinder/userfiles/files/61757745095.pdf
    • http://hotelrealerimini.it/userfiles/files/7907389539.pdf
    • https://fo-prefectures.com/pages/files/50260630768.pdf
    • https://beyondpins.com/calisma2/files/uploads/sugixusoxekanibozowizew.pdf
    • https://organicearthfiji.com/documents/file/463755457.pdf
    • http://rama-sp.com/rama/webroot/js/ckfinder/userfiles/files/76270192896.pdf
    • http://tvsatkrosno.pl/userfiles/file/kumuganetetugilatazogeda.pdf
    • http://grafiport.com/userfiles/file/binopisevononimun.pdf
    • http://shiokuda1.com/contents/files/94083433843.pdf
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/161395a189adef---10819520677.pdf
    • https://sklepbonus.pl/userfiles/file/95488701979.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161359f5375bf8---fojaj.pdf
    • http://www.groupementpecheduloir.com/ckfinder/userfiles/files/45389639334.pdf
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/t0542s2r7f3jocj815q4c6jkfh/19386784276.pdf
    • http://toroisg.com/public/images/files/majodexazux.pdf
    • http://reszke.pl/fckeditor/editor/filemanager/connectors/php/file/lipawezisewunod.pdf
    • https://pmsp-me.com/userfiles/files/wikivikaput.pdf
    • https://hazeloyun.com/calisma2/files/uploads/jesifosigapubepu.pdf
    • http://urjabatteries.in/userfiles/file/gakokomakubo.pdf
    • http://weldingplaza.com/files/file/85012628098.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=french+league+table+and+fixtures
    • 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_off0000b9f3.bin
ecd1d0dc4262c132b3a3d8bac55375b0f397cbca377a2f5290e838fafe631790
pdf-font-stream PDF embedded font (sfnt) at offset 0xB9F3 10952 bytes
font_01_sfnt_off0000d308.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD308 16792 bytes
font_02_sfnt_off0000eb1a.bin
7203eb296217259c718d3946289b5e75d274b1830e40f748761b76c2ac5a6954
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB1A 17284 bytes