Malicious PDF — malware analysis report

Static analysis result for SHA-256 23d5eef6fb039453…

MALICIOUS

PDF

78.4 KB Created: 2021-06-09 14:49:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 476c02aacacd2d3960fc773d94759dd0 SHA-1: 400a9c6e6ba946bb9440fbdc56e995d2ad1d92b8 SHA-256: 23d5eef6fb03945398860b46ec1c8424d8202477cafdb166e465376930f329c4
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable hosting, suggesting it's part of an SEO spam or phishing campaign. The embedded URLs and the document's structure strongly suggest it's designed to redirect users to potentially harmful sites, possibly for credential harvesting or malware distribution.

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://philabc.ru/pbw?utm_term=illustrator+calendar+template+2021 PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4388065/normal_5ff612cbc2d10.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425256/normal_60bad6dc8baa2.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4469350/normal_5ffc31cda9383.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4371025/normal_5fe04c06a3c2b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4480142/normal_5fdd5ab7d39ec.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448357/normal_60bd4bcd2b1d8.pdfIn PDF document text
    • https://jolevodib.weebly.com/uploads/1/3/1/6/131636654/4223461.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366623/normal_600d978623af4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387577/normal_60621c63e5f79.pdfIn PDF document text
    • https://rilofiwidipu.weebly.com/uploads/1/3/4/4/134455443/kagag-dusozaw.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403689/normal_60606cac370d7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425235/normal_6015399393464.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489607/normal_5fe64c7c891a4.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://mumasenekera.pbworks.com/f/pitetanamaxisumawage.pdfIn PDF document text
    • http://felefejimax.pbworks.com/f/finding_area_of_irregular_shapes_worksheet.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ac61f0dc-a68f-4791-bc5b-a2e26e0f8c82/betukimogowirolugitavafeg.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6d75be31-8483-4d3e-9d9a-0cb2c08e5582/vipowopibuxuwo.pdfIn PDF document text
    • http://jizakatum.pbworks.com/f/computer_operator_jobs_mcqs_with_answers.pdfIn 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_off0000e7fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7FC 5316 bytes
SHA-256: f20c1a9dfde23e4d01cebc2823048e0271562e8470001b05c71c7c254e867831
font_01_sfnt_off0000f9ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9EC 10572 bytes
SHA-256: 97334111a53fe303ab98d340e82055980373088818a2160711f1c916ba793fc9
font_02_sfnt_off00011e3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E3B 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176