Malicious PDF — malware analysis report

Static analysis result for SHA-256 8505d0cc6a2e996b…

MALICIOUS

PDF

85.1 KB Created: 2021-07-06 14:24:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4ce3454adb538ebdb56b884eb907a714 SHA-1: 67690b3abc0d591fae0c0a6cc0cdd422ec1b1f46 SHA-256: 8505d0cc6a2e996b1e27422f86d019f14a7fb36be65cf5bead0d6a8d5d8bbaad
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or delivering malicious content. Heuristics indicate the PDF acts as a link farm, pointing to compromised WordPress upload storage and other disposable hosting, suggesting an attempt to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://rzfmuhasebe.com/userfiles/file/97143862583.pdf
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b6504d03859---zogix.pdf
    • http://saopauloairporttransfers.com/ckfinder/userfiles/files/61232630227.pdf
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608965237b732---gevekemivaxelivofapuvipaj.pdf
    • http://pokemom2.com/uploads/files/lajumasenelenijitujavan.pdf
    • https://benqmusicworkshop.com/fupload/file/vajegoniza.pdf
    • http://monkey-do.net/userfiles/file/lenenote.pdf
    • https://baxsporthorses.com/userfiles/file/21408590144.pdf
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c8d1732d85a---padolib.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16081b5f9526be---galopepimij.pdf
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f8e105557d---gopomumibuxobifobajaneb.pdf
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d3ce60e4d56---zozafesujoguvaxi.pdf
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/59254bf8f46effbda287fcd9abbbb818/64733024155.pdf
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/e88582ff0517c4543d3522dc342d28e3/11509768545.pdf
    • http://kappp.ru/js/ckfinder/userfiles/files/siziwamegofevup.pdf
    • https://slezanie.eu/userfiles/file/mutepowigoxuluximizames.pdf
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/160b34620736b3---38351145816.pdf
    • https://yarpaket.ru/userfiles/file/36913848678.pdf
    • https://nhatngudongkinh.com/upload/ckupload/files/vazen.pdf
    • http://dieta-plus.pl/userfiles/file/86746192877.pdf
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/160c039f94329f---wuxetowanagowuki.pdf
    • https://tractorpulling-emmeloord.nl/upload/file/toxirokipumefonawoxumepu.pdf
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1607bc35ed1483---7908487420.pdf
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608077401729a---97065944980.pdf
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/8cdff474462960815cd9fd2c97f4510f/jonetivawusosolisoz.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=university+of+pittsburgh+tuition
    • 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_off0000e982.bin
f2f22dfc126eb9c3492b9fe70446bce571ff8be72c453f5911beb6e7dee4f164
pdf-font-stream PDF embedded font (sfnt) at offset 0xE982 17016 bytes
font_01_sfnt_off00011613.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11613 16792 bytes
font_02_sfnt_off00012e2a.bin
62e0fa13313af8efc1695135e3782fd934b09cebed9812411ec91c1c6145ddf2
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E2A 10856 bytes