Malicious PDF — malware analysis report

Static analysis result for SHA-256 34b2c6ff6d157654…

MALICIOUS

PDF

71.3 KB Created: 2021-06-14 00:01:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 9fb23100cabf294b545b44776234e5d4 SHA-1: 93fbdb9380694da5d4c70a073c310415b278c0cb SHA-256: 34b2c6ff6d1576540068ecebd9ccb2239ff875997e7a87b9fcd04af465529a85
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://chcial.ru/uplcv?utm_term=hponcfg+download+windows PDF link annotation
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/160b27e0757363---30373153943.pdfIn PDF document text
    • http://rauvuonsach.com/images/uploads/files/rowotujajusarokufebeka.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e4833a72b4---11131310753.pdfIn PDF document text
    • http://nhs1980alumni.com/clients/878257/File/fudotujenepipalosu.pdfIn PDF document text
    • https://luyenthitoeic.info/userfiles/file/16515492220.pdfIn PDF document text
    • http://strandedtattoo.net/file/bijaxepipozaridabukaxew.pdfIn PDF document text
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/f2bc68d2f49d03017d5edbd569a3b120/sarowes.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b1b89e75ba3---85916311513.pdfIn PDF document text
    • http://kasargod.net/uploads/file/xamamikididizo.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c46ca47ac7---rufiwojorusivivijumitox.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c344b163e1e---daligebelobupisovideg.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3928d190ce---80534439750.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-5-25/20210525045357980586.pdfIn PDF document text
    • https://cochleartudaskozpont.hufiles/94094729938.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/f1c551d9070435aaa01c46c200a3040a/zajerak.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_off0000d9f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9F2 5280 bytes
SHA-256: 0ae4f08f208f4c6bd996f55ab2a8ab77845139434bdd3cc7f7dc98c7c2c6f192
font_01_sfnt_off0000ec15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC15 10760 bytes
SHA-256: ac5bc6bc1eb43b2441edc17cf8685fd7a3b2561f13ba24ca524fe7d0f299e049