Malicious PDF — malware analysis report

Static analysis result for SHA-256 e6b66c91dd334db7…

MALICIOUS

PDF

88.4 KB Created: 2021-09-15 22:17:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 05b59d8a08951d8a00769b1286abc275 SHA-1: 4c9eee8a08246937b8f7a5f1291d6e90e719fedb SHA-256: e6b66c91dd334db717b41f257eeba892860479175d36b12976dffb386dbf767a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports the assessment of a link farm on potentially untrustworthy hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://netlandschool.cl/files/5605897897.pdf
    • http://veszpremkosar.hu/_user/file/89258396567.pdf
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/16131e26f1707f---luwilosolosilakop.pdf
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/ddaea114e63ff79f33340ed6ca7ba73e/nigenipusigoseka.pdf
    • http://tfforming.ru/d/files/zarokefetit.pdf
    • http://fullerton.kopanramen.com/uploads/files/kowekeboravarenuk.pdf
    • http://gallery4walls.com/upload/editer/file/roredabipunurusivojorune.pdf
    • http://portalpr-b2b.es/img/user//file/_0903431001630795055.pdf
    • http://www.verneteco.com/ckfinder/userfiles/files/6358795441.pdf
    • http://spec-so.ru/sites/default/files/file/2332827831.pdf
    • https://funbugs.ie/files/file/71651022531.pdf
    • http://esipro.fr/userfiles/file/bideta.pdf
    • http://makassitools.com/userfiles/file///konafuwutigazeb.pdf
    • https://vzglavniki.net/data/file/gitovini.pdf
    • http://sunnysolutions.it/uploads/assets/file/zujubidinobulugemodekupu.pdf
    • https://asztromiskolc.hu/ckfinder/userfiles/files/netutozovogofak.pdf
    • http://georgekoldun.com/var/upload/file/tomupuxotilavamaderuxog.pdf
    • http://sdds.be/userfiles/file/zugapuvuvodazolubi.pdf
    • https://foodexgida.com/uploads/files/zolifukubifolike.pdf
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/7sk0q2es1fc8vtf8k0khc4k24u/vakexogibamopob.pdf
    • http://hexindechem.com/upload/files/kowawolite.pdf
    • https://armature.ir/cache/fck_files/file/mowakulu.pdf
    • https://ksdc.in/userfiles/file/wosodimumexar.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=game+open+world+rpg+android
    • https://b2cdemo.tickets.com/content/files/21353445109.pdf
    • 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_off0000f7c1.bin
ed11dfb772807cdc3ea0a8c1e46d9df5fb51d900124c3150c31d22d5d08570ac
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7C1 10592 bytes
font_01_sfnt_off00010fa9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10FA9 16792 bytes
font_02_sfnt_off000127bb.bin
9bfd9bcde4b44bfc3b20865141e1410d35ece8156dd49fa60344a136ba9fbea5
pdf-font-stream PDF embedded font (sfnt) at offset 0x127BB 16936 bytes