Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5a5f9726a23cf51…

MALICIOUS

PDF

78.8 KB Created: 2021-03-30 05:21:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-02
MD5: 39ae82c626fc3a1609e1ba39a1e2bd79 SHA-1: ebead3b83edaf65f831c8cd15b1c4ed4f36e9492 SHA-256: e5a5f9726a23cf51ca8ae82d8944f455ff29107fa389f67afcc1c88abf945873
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, suggesting a link farm or phishing operation. The ClamAV detection and ML classifier strongly indicate malicious intent. The document body, though heavily obfuscated, appears to reference '500 essential words for toefl pdf', likely a lure to direct users to malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://pelibifir.ru/strik?utm_term=500+essential+words+for+toefl+pdf PDF link annotation
    • https://fuwurukuzubefek.weebly.com/uploads/1/3/0/9/130969433/pukudesi_zepizexi_wapegod.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4370053/normal_600102841590c.pdfIn PDF document text
    • https://cdn.sqhk.co/wexunaveb/gfjeicc/52926095129.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447095/normal_6023ce421ede6.pdfIn PDF document text
    • https://cdn.sqhk.co/musezikuzapi/hgfiajX/cheesecloth_dress_missguided.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418385/normal_6026786abe42f.pdfIn PDF document text
    • https://sokepubin.weebly.com/uploads/1/3/5/3/135391759/xusimoduko-fesipuwakijepa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385876/normal_605b22041462b.pdfIn PDF document text
    • https://zevupumogejaju.weebly.com/uploads/1/3/2/8/132814041/wejufi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/ec6e8ae3-dcad-4c76-a330-74cca29c7f10/how_to_become_a_certified_medical_interpreter_in_washington_state.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e0c25160-79da-4bf7-9d1a-2b4966b06d08/fifetivabemifidiv.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/818796c5-14a3-446e-a7c2-4d647066c82b/zodeko.pdfIn PDF document text
    • http://bitizadixiriwen.epizy.com/orthographic_views_to_isometric_drawings.pdfIn PDF document text
    • http://kasarokoxakuke.epizy.com/latest_android_version_huawei.pdfIn PDF document text
    • https://s3.amazonaws.com/meludav/42930566539.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8b943417-7e00-40e9-9365-59b384606137/rilanevo.pdfIn PDF document text
    • http://wororapuwubetuv.rf.gd/vevemix.pdfIn PDF document text
    • https://s3.amazonaws.com/gedexim/96927628454.pdfIn PDF document text
    • https://s3.amazonaws.com/gaxuremewuger/metro_2033_redux_library_guide.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/119bdd06-14d1-4ae9-a55c-9bd54c6d55fb/present_perfect_exercises_intermediate.pdfIn PDF document text
    • https://s3.amazonaws.com/nuxomigo/adanga_maru_tamil_movie_hd_tamilrockers.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e7af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7AF 5296 bytes
SHA-256: 8fffa037daffe3d634713cee421ed922a3c269addcf8c47234d29ec7c0c44e8b
font_01_sfnt_off0000f9d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9D8 21248 bytes
SHA-256: 003234cae282fbb304818afc537147aeed30afe0d60e86867481758c32aac659