Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c8f597bdd3f5926…

MALICIOUS

PDF

87.0 KB Created: 2021-07-19 08:19:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 42fa742d0dd08456e5eed25a7f17e6a4 SHA-1: 9c0247969f69b144fe4d99385e27bda0eeb3f203 SHA-256: 9c8f597bdd3f5926ed5cfd3f2a99c1799ca4201ed2f46afe16c40e4fc3afc55a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file containing embedded JavaScript, which is a common technique for executing malicious code. The PDF also features a link farm pointing to compromised WordPress sites, suggesting an attempt to distribute malicious content or redirect users to phishing pages. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/88396711366d721c047ec256c1e81e2a/momodaxine.pdf
    • http://alemotta.com/resources/original/file/74724383405.pdf
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/d7c148nplh6dksmhf4m5196hu3/54531586959.pdf
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16087dd8d5a418---dubekomukipirop.pdf
    • https://cald-lighting.com/wp-content/plugins/super-forms/uploads/php/files/b2a47c91f64dccfeda38bf1412206d80/21732093380.pdf
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/900862a2250b60d388cab9033c84aacb/vopepukanesone.pdf
    • http://www.mezmat.ru/ckfinder/userfiles/files/kumusorewovezasozige.pdf
    • http://euhoca.com/js/ckfinder/userfiles/files/8494691171.pdf
    • https://migger.dk/userimages/file/15933059223.pdf
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/dfae5784e36f09ba8256ae84213dc7d4/vuresesuropipa.pdf
    • http://bookblog.kr/data/file//files/vubagarukavanezajupiwufe.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/160e13d556f7b7---76203343515.pdf
    • https://foxtailmag.net/wp-content/plugins/super-forms/uploads/php/files/2dab016d4ecab8647c2127212110753e/gokewanefoxuzevapiroseri.pdf
    • https://zoomkish.com/basefile/zoomkishcom/files/91139019532.pdf
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/0i312v34bns19l14vqeo2159p0/fekejenasugagelozegubok.pdf
    • http://smflow.in/admin/uploads/file/jevafivowinal.pdf
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/fsfvptvt2ad01uviq5uiq6fm6u/45326643521.pdf
    • http://lev-steklo.ru/userfiles/file/10338045596.pdf
    • http://agcslohian.com/userfiles/file/86063096203.pdf
    • https://angkorphotographyguide.com/userfiles/file/gawonivavimewu.pdf
    • http://bestbelly.org/content/files/files/70071691025.pdf
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/d406646d153b7cad24751014a12840c1/gizigatosivuzezu.pdf
    • http://al-bandak.com/userfiles/file/pozefipiximogomawe.pdf
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160d2b0fad83f4---43173911663.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=removing+loc+extensions
    • 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_off0000f122.bin
eb7056d9b4abfe003a03dc47afd766c1100c5d306c7bdf34c7c5c157ad64dbf4
pdf-font-stream PDF embedded font (sfnt) at offset 0xF122 10524 bytes
font_01_sfnt_off0001091b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1091B 16792 bytes
font_02_sfnt_off0001212d.bin
088d186c493b2552b5c71644af3ed6db0e78dbb144bdbd857ef8c6275ac53455
pdf-font-stream PDF embedded font (sfnt) at offset 0x1212D 17476 bytes