Malicious PDF — malware analysis report

Static analysis result for SHA-256 ce5222c25abbf23e…

MALICIOUS

PDF

76.7 KB Created: 2021-09-19 08:32:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 632e045b060269b043ff92712f8d0339 SHA-1: 66da9d11613b282d9593574194013bfa59e0e190 SHA-256: ce5222c25abbf23e699ae542a9c7db2cd0e2d4e79de428a166d51ac0db38a8ef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The document body is heavily obfuscated and appears to be non-readable content generated by wkhtmltopdf, suggesting the primary function is to host these malicious links rather than convey information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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://ctcitsupport.com/media/files/71282585492.pdf In PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/pdcnibk0d1mrrclv24ru8rld90/livuben.pdfIn PDF document text
    • http://westhollywood.ilovepokebar.com/uploads/files/92338518281.pdfIn PDF document text
    • http://savaksangida.com/resimler/files/ragepudewarufapuj.pdfIn PDF document text
    • http://myoffice2561.sesao33.net/UserFiles/File/fetoporinefaza.pdfIn PDF document text
    • https://artenika.pl/fck/file/pizumofonukaxebiselewab.pdfIn PDF document text
    • http://instit.ac/ckfinder/userfiles/files/basilowefirofawe.pdfIn PDF document text
    • https://anukulagrotech.com/ci/userfiles/files/16234000496.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613939187de89---rogepo.pdfIn PDF document text
    • http://asfalon.com/__files/file/xetubarewojulu.pdfIn PDF document text
    • http://cbcom.fr/ressource/site-image/files/56546556874.pdfIn PDF document text
    • http://multi-accueil.fr/ressource/site-image/files/87161189564.pdfIn PDF document text
    • http://www.childofafrica.org/media/userfiles/file/joritududeborubil.pdfIn PDF document text
    • http://shangrilatheshow.com/ckfinder/userfiles/files/68144230159.pdfIn PDF document text
    • http://biomehl.com/images/content/files/2126529335.pdfIn PDF document text
    • https://4of100churchstreet.com/assets/media/files/labawaremareluzufivatoxi.pdfIn PDF document text
    • http://oprandi.it/userfiles/files/75806438551.pdfIn PDF document text
    • http://dlastudenta.org/Upload/file/92126475507.pdfIn PDF document text
    • http://ed-union05.ru/files/file/ragonivimosibogojige.pdfIn PDF document text
    • https://aprilboya.com/userfiles/file/65410886133.pdfIn PDF document text
    • https://dukra.sk/editor_uploads/files/52464565147.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141da83aa04d---80608466009.pdfIn PDF document text
    • http://reguitti-engineering.it/userfiles/files/30699609924.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/6p6tkooptfkd4jo510jn0a9ak4/fuvali.pdfIn PDF document text
    • http://www.blueoak.fr/image/file/21761613555.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=warhammer+40k+9th+edition+pdf+freePDF link annotation
    • 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_off0000c510.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC510 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dd27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD27 11000 bytes
SHA-256: e76072029bf6477157fbca4955562aba5b8e68a654f398b3e29e6e397c270279
font_02_sfnt_off0000f68b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF68B 17964 bytes
SHA-256: 90030b0e2b637696988fdcc12010eb2ba3df0fb7edd859044cb0cc5be3123858