Malicious PDF — malware analysis report

Static analysis result for SHA-256 d16b10c214db9b79…

MALICIOUS

PDF

65.8 KB Created: 2021-06-23 19:23:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: c43757778360a51a5705b2abafee0517 SHA-1: 259508efc0a041c9549930632b233c76241fce29 SHA-256: d16b10c214db9b79c393ccf74a4ec0a1f1d5fbe1e7932c5bf3593c0f87546485
156 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains numerous external URIs and link farms pointing to compromised WordPress upload storage and disposable hosting, suggesting a phishing or malware distribution campaign. The presence of these links indicates an attempt to redirect the user to malicious content, likely exploiting a PDF vulnerability for client execution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://ketchas.ru/uplcv?utm_term=p8031ah+intel+pdf PDF link annotation
    • http://syuncyoku.jp/upload/file/mobesigosotewamoretes.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608ac11fb4015---sufenuxulud.pdfIn PDF document text
    • http://lighthouseofworship.com/clients/44803/File/5490310513.pdfIn PDF document text
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b6ffec5711a---mamuvepovavitebujuravi.pdfIn PDF document text
    • https://mrmusicfoundation.org/wp-content/plugins/super-forms/uploads/php/files/quufhlm9emqaku59v6a2lftmi3/refenudimixaj.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608774335802e---79307581151.pdfIn PDF document text
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/845596afc83b7a26d6adcff9b1b039c4/28259940476.pdfIn PDF document text
    • http://voxel-avocats.fr/uploads/file/desujerufomotek.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be9f1131845---xixobasijujuvelo.pdfIn PDF document text
    • http://theofficefurniturestore.com/ckfinder/userfiles/files/17231888365.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/83d7f7a92ca4ce692cf949a85719bd41/86170822086.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/89d8a3a4435311229d7fd7300aed394e/vupanodixa.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160960edb33375---91938468965.pdfIn PDF document text
    • http://topas.lt/userfiles/file/tezutewajaxap.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/2e0e5ae09e9433523379ce9311c216b8/535153934.pdfIn PDF document text
    • https://www.saammohaseb.ir/wp-content/plugins/super-forms/uploads/php/files/26ff5ce703487514dc046fe4955c000b/jafijudijobawita.pdfIn PDF document text
    • https://www.llgnjinc.com/wp-content/plugins/super-forms/uploads/php/files/afbadec0587a58936f59e8d0cf106ccf/31326307600.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c51e8fb5d71---rijibalumanufitefetevak.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c08b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC08B 5408 bytes
SHA-256: a24067e0d7fb51245107a2365195c6b4d0b46a80973b15ac1bcc973e59a02798
font_01_sfnt_off0000d2fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2FE 12496 bytes
SHA-256: de4c0cd1d787a2b97ebf799a334b9103c3577bc44e8e5103897c379b806ba39f