Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c1311dd107d77e5…

MALICIOUS

PDF

72.9 KB Created: 2021-09-23 05:38:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 1813311f423eabe481fddde1b3f19541 SHA-1: b490964c5a1ad03e247908889565d20cef871710 SHA-256: 3c1311dd107d77e54c44967019775f75dc476af1d8ed6037cf0a30846ddda1b1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised CMS platforms, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to malicious content or download further payloads. No scripts were extracted, but the PDF structure and URL patterns are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://huntic.ru/uplcv?utm_term=oet+reading+material+pdf+free+download PDF link annotation
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16149189b19cf2---batinamumutazamibigif.pdfIn PDF document text
    • https://open-call.fr/uploaded/files/baxuviniwedimode.pdfIn PDF document text
    • http://falconartistmanagement.com/ckfinder/userfiles/files/50623175580.pdfIn PDF document text
    • https://clinicamanila.com/ckfinder/userfiles/files/mutazepesubu.pdfIn PDF document text
    • https://arsenev.verlauf-ekb.ru/admin/ckfinder/userfiles/files/11342122039.pdfIn PDF document text
    • http://karpzbeldowa.pl/uploads/userfiles/files/benomotofenuvidijuruf.pdfIn PDF document text
    • https://biocenfis.es/uploads/assets/file/fivizezenefugem.pdfIn PDF document text
    • http://m-camper.ru/ckfinder/userfiles/files/bijiza.pdfIn PDF document text
    • http://volkshilfe-vlbg.at/images/content/files/bibataxapevatazil.pdfIn PDF document text
    • http://cermak-expo.cz/data/files/file/22921217827.pdfIn PDF document text
    • http://tinhdauvietnam.vn/upload/files/gewogugerugokejere.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613df8103a51f---bawexajezilet.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/salovikudutaxuruvupi.pdfIn PDF document text
    • http://mh-gartengestaltung.de/userfiles/file/38629159443.pdfIn PDF document text
    • http://bacvietexpress.com/upload/userfiles/files/27101516079.pdfIn PDF document text
    • https://g4m3s-4p1-12s1.com/contents/files/88759015195.pdfIn PDF document text
    • https://yellowstonewildlife.com/62558996500.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613dd40e08b71---ziwokegodifubutupomofof.pdfIn PDF document text
    • http://shopgraeagle.com/ckeditor/uploads/files/karivujaja.pdfIn PDF document text
    • http://olynskiconstruction.com/pics/file/2006082656.pdfIn PDF document text
    • http://sireny.net/share/files/gagasilotaxufemumaro.pdfIn PDF document text
    • http://zentrumok.com/userfile/files/rubesekomimoni.pdfIn PDF document text
    • http://naturallabs.de/userfiles/file/godabodimebamogopojumux.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b916.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB916 17032 bytes
SHA-256: 37fae9b89c67048178a8cdc79ed346044cb6d41c49d6507def7ce9b595878bed
font_01_sfnt_off0000e52e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE52E 10784 bytes
SHA-256: 405fa3dd049c44ddf85de2116d1279bee3113944901f1a7109a82d0b5aee1d8a
font_02_sfnt_off0000fdd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDD2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1