Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd761c8d42ec413a…

MALICIOUS

PDF

93.0 KB Created: 2021-02-16 06:13:39 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 770b8097d3da0e8c00df864b59d61886 SHA-1: 4c1a8f424bf2b02b038f7cc40e1606593e78ab4d SHA-256: fd761c8d42ec413a06d1dea91620e1de0f78a9412d0bb8d47f7c8e7c05f31488
214 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are identified as part of a link farm or redirect to malicious infrastructure. The primary malicious URL identified is https://yafferge.ru/wix?keyword=speak+mandarin+in+1000+words+pdf, which is likely used to phish users. The ClamAV detection and ML classifier further support the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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 links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/wix?keyword=speak+mandarin+in+1000+words+pdf In PDF document text
    • https://bakasilamor.weebly.com/uploads/1/3/1/4/131407315/731b454580d4.pdfIn PDF document text
    • https://cdn.sqhk.co/patagarinixa/itgdgcF/samuhik_smart_appearance.pdfIn PDF document text
    • http://xebajar.22web.org/adverbs_of_frequency_worksheet_for_grade_1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.opentle.orgIn PDF document text
    • http://lugubukegi.epizy.com/54618951482.pdfIn PDF document text
    • https://s3.amazonaws.com/rilexazejuzovep/95932847157.pdfIn PDF document text
    • https://s3.amazonaws.com/begijufadi/barbie_doll_values_guide_book.pdfIn PDF document text
    • https://s3.amazonaws.com/golepe/rajukefemevivipegela.pdfIn PDF document text
    • http://kijenor.epizy.com/coroners_court_nsw_reports.pdfIn PDF document text
    • https://s3.amazonaws.com/minaxigevani/durokovojavi.pdfIn PDF document text
    • http://budobilososuw.rf.gd/answer_key_prelims_2019_set_b.pdfIn PDF document text
    • https://s3.amazonaws.com/nedijowewoded/graftech_international_ltd_annual_report.pdfIn PDF document text
    • https://s3.amazonaws.com/sefiwegegagu/zibepejatuxazinafu.pdfIn PDF document text
    • http://baduwujik.rf.gd/intellectual_capital_australian_annual_reporting_practices.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
    • http://www.gnu.org/licenses/gpl.htmlIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d5f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5F7 17736 bytes
SHA-256: 8a19de42edc00fd6a6d9cfd2b01e7fcded0b9072f6dcac47dd898dcfed4cf3c4
font_01_sfnt_off00010d60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D60 5608 bytes
SHA-256: 7698108ba0088d24bab24a5bf66ef83ef20fc54f1c2b0d78e05df20c74b79e74
font_02_sfnt_off0001206e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1206E 7716 bytes
SHA-256: 8cb07919fc89104251fe583d07f88e29f4eae0134a1d720473836a41389a17af
font_03_sfnt_off000135a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135A6 15660 bytes
SHA-256: 1fa19a73f7ecd7d7b8d62bd76fd2a96b476de0a9bc1a66e2c9a8b89ebe09ab09