Malicious PDF — malware analysis report

Static analysis result for SHA-256 1e9be8681df535b6…

MALICIOUS

PDF

77.9 KB Created: 2021-06-14 20:54:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 9c8ea2d02a9b2666e71f3f552a29da24 SHA-1: e473a1fdfe8ab0b92b3e5ada96f37d293bf53ed8 SHA-256: 1e9be8681df535b619d66dcf4cad11ef69c2857f405df0a7a40851e5b4d4d2d2
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://oniceh.ru/uplcv?utm_term=neetu+mam+english+book+pdf PDF link annotation
    • http://quickvideo.nl/userfiles/file/gaweva.pdfIn PDF document text
    • http://anandamsanyal.com/userfiles/file/rowafafenopixalo.pdfIn PDF document text
    • http://chinocorporatechallenge.com/clients/6216/File/93657411928.pdfIn PDF document text
    • https://prikolnaya.com/wp-content/plugins/super-forms/uploads/php/files/34a38b524f40e16e1bcef1029fe1bffe/702682631.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/ec5d6be4edce2ace2c0fd8dfdd8a7bb8/futinaxenagesenajakenafok.pdfIn PDF document text
    • http://progfin.pl/userfiles/file/buvejupuzoxeduf.pdfIn PDF document text
    • http://sillajen.com/fckeditor/_upload/file/1285562267.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c0f4604afca---70205926796.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/m0r4lsafdckpo64fv07qmpav4t/foluponagaxifepejatadipus.pdfIn PDF document text
    • https://nnkcreations.com/userfiles/file/18596559281.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b0525a4d9e7---89837270571.pdfIn PDF document text
    • http://ahlhy.com/uploads/file/051001477214.pdfIn PDF document text
    • https://reflexlighting.com/wp-content/plugins/super-forms/uploads/php/files/28b473dd6526baee8a1ff6449077c8c5/paxidu.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a318ba53cf6---pifilosukazutopogib.pdfIn PDF document text
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/80a1d876c13b8050c2854da6ec9f055e/71310722318.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fedorahosted.org/lohitIn 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e77b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE77B 5532 bytes
SHA-256: b8c6f530a22a2ee6335c4c8996572496341eaf411a46828f444f3e786666d9e8
font_01_sfnt_off0000fa26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA26 10512 bytes
SHA-256: 08c810a91f61f117c95f0418c85c4d0774e22418dbd731428293af498fab6ad1
font_02_sfnt_off00011e41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E41 3096 bytes
SHA-256: b36887c4a7c7a3433e89771280e832680810e4ebd2b7337407c7dbe608e95547