Malicious PDF — malware analysis report

Static analysis result for SHA-256 728772bb13ee888c…

MALICIOUS

PDF

90.9 KB Created: 2021-08-03 06:15:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e6a5d41258952a56b039b5f3f7da3148 SHA-1: 90131e2380afd87963655dee3628be6ae113e1bd SHA-256: 728772bb13ee888c33f8cf495dc0636f6dd93bd77e6613c2108a3ddd2e6e3d98
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for executing malicious code or redirecting users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9932

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://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d9486fa22d5---68091005825.pdf
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160904c2ee1f5f---651940963.pdf
    • http://www.proyecpapel.es/ckfinder/userfiles/files/60948828061.pdf
    • http://kfnmsz.com/upfolder/e/files/20210709114134.pdf
    • https://i-chat.tw/js/ckfinder/userfiles/files/55956333150.pdf
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b334fd08e49---16892176227.pdf
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/66f8eb83f5a49f776c2f72692660751c/daxaxom.pdf
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609257478b14c---47001912761.pdf
    • http://toyotacri.com/userfiles/files/muzuxudu.pdf
    • https://garyjetcenter.com/wp-content/plugins/super-forms/uploads/php/files/3d6829b8d8ebc110f7baddcfd2e0533b/jerilixasizi.pdf
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160795bd0a7f0e---gebarur.pdf
    • https://dermatologie-chamonix.com/userfiles/file/zuzisakaj.pdf
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/abacae5dc0c678e8ca0bb11cecd7b14e/polokugoxapofe.pdf
    • http://brenna-ski.pl/userfiles/file/tuzadugolunopelas.pdf
    • https://angelsstaff.com/uploads/file/97613086677.pdf
    • http://dichvu12h.net/userfiles/file/67864163764.pdf
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/sk34ckobhd2ie8uk1a2giniqv1/69988784362.pdf
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a8cf5c94340---22115310245.pdf
    • https://www.frontiermea.com/sites/all/libraries/ckfinder/userfiles/files/19422047867.pdf
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607465474cf5c---99431906715.pdf
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/e630a4fc52ed355ccb8d627367ab1175/42337516937.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160740abf111e1---21701868547.pdf
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160da5872a891f---pamube.pdf
    • http://csc-020.com/userfiles/file/20210702220930_vdoml8.pdf
    • https://kopari.hu/files/file/8005834596.pdf
    • https://allmassage.net/upload/file/20210505063046.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=modern+physical+organic+chemistry+pdf+free
    • 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_off0000fb8f.bin
a09d33dc6f80fb8794e34be5ec4ef77cb822fdc6b14cb70860e6e7773fcae068
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB8F 18376 bytes
font_01_sfnt_off00012b08.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B08 16792 bytes
font_02_sfnt_off0001431f.bin
985c406e9a7a19467f130b7cd3a0d796d7fe4716ff36c8d1f06e2da65fdda136
pdf-font-stream PDF embedded font (sfnt) at offset 0x1431F 11176 bytes