Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd26416d28215795…

MALICIOUS

PDF

72.5 KB Created: 2021-06-21 18:24:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 289d5966ccdbce7ded9083a243fe794a SHA-1: d789fa2fec0efe06df58a05a0ad591a69d380bcd SHA-256: cd26416d2821579514fadfc4c0b627a9102bcff84112c6c3a9ffcff8680014ab
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised CMS platforms, suggesting a phishing or malware distribution scheme. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, indicating the document is designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://oniceh.ru/uplcv?utm_term=history+and+civics+class+7+pdf PDF link annotation
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/9f79af21bad00df4d674a47168cfd534/55294052984.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/006cb27a273d734a5ba45d2b6508fb1c/topomilusumutegunoxep.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/7cdfb8d4f82f7deeb04c09ab8f25a73a/pupibex.pdfIn PDF document text
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/a05ce7df7f81ec35332e156a62cb9dda/77372152956.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/44714535567.pdfIn PDF document text
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/tl6q59mv8nj03ovb8bhcotllg3/21113660599.pdfIn PDF document text
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/49737972f24a35fbaf6e45d6c83082c8/18058078444.pdfIn PDF document text
    • http://extracam.es/app/webroot/arxius/file/lufojabele.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b34e1ee93e---xofavolavig.pdfIn PDF document text
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/7vh2g87lu8son9hvvsqpbk9ob1/tefalamuz.pdfIn PDF document text
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/4c1b3cca085b94c7b26ad0286fcf93a3/90989524171.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160963309cafe3---buwub.pdfIn PDF document text
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/abebaf74133384d887c9c947859e6a33/fexagegawuko.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_off0000cbdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBDB 5352 bytes
SHA-256: 3c423867f2b1dd5b4f13b7f3146b1c342cf878ac11cfa347d3202a77e06a5647
font_01_sfnt_off0000de32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE32 10428 bytes
SHA-256: 2bdb40b0a57cf02d35098a667452a724b4fa9880ee4e9524e7c6c8d1dee79748
font_02_sfnt_off000101e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101E2 4748 bytes
SHA-256: db72dbfb1394f62a03d492c7bd90abaee0f3c566940e96956514dbea5e4a1aca