Malicious PDF — malware analysis report

Static analysis result for SHA-256 78ea0c3381bc1843…

MALICIOUS

PDF

78.0 KB Created: 2021-04-06 02:26:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f94b4b602bd3f0247e6508d763cbdfeb SHA-1: 72aa51f0de3eca96ad955319630e5e767cb5f9eb SHA-256: 78ea0c3381bc1843f5232414923c5958bf31be099c57fbaf9ea1edf7a53c594a
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by multiple heuristics and a machine learning classifier, with ClamAV detecting it as 'Pdf.Phishing.Trojan'. The file contains a large number of external links, indicating a link farm strategy, with one prominent URL being https://ponafet.ru/strik. The presence of embedded URLs and the overall structure suggest an attempt to redirect users to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://ponafet.ru/strik?utm_term=what+is+tcp%252Fip+model
    • https://static.s123-cdn-static.com/uploads/4388160/normal_60081e862934e.pdf
    • https://gepufefodu.weebly.com/uploads/1/3/4/0/134013389/2112695.pdf
    • https://cdn-cms.f-static.net/uploads/4481671/normal_6026a47758fea.pdf
    • https://woxolifufoku.weebly.com/uploads/1/3/4/2/134234665/zesitajogajosadedus.pdf
    • https://cdn-cms.f-static.net/uploads/4368504/normal_60293eb6af402.pdf
    • https://cdn-cms.f-static.net/uploads/4453532/normal_6009dc89cf370.pdf
    • https://static.s123-cdn-static.com/uploads/4472484/normal_5fec3fbb824d8.pdf
    • https://cdn-cms.f-static.net/uploads/4463824/normal_605708923a37b.pdf
    • https://mizabago.weebly.com/uploads/1/3/5/2/135299272/balefalaveletiruto.pdf
    • https://vebilikowuti.weebly.com/uploads/1/3/2/7/132740371/puwariwexuxid.pdf
    • https://cdn-cms.f-static.net/uploads/4413228/normal_6035cb9fd0469.pdf
    • https://cdn-cms.f-static.net/uploads/4493266/normal_60637c9e1197a.pdf
    • https://cdn-cms.f-static.net/uploads/4371267/normal_6055b959b52a6.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cf176ec6-4820-456b-adf9-61e5f06c968f.filesusr.com/ugd/43d598_4dfed57e897b461386ccd5ead0a809a8.pdf?index=true
    • https://91c7bc9f-df77-4dbd-ae51-8bcf521f3e61.filesusr.com/ugd/1df9ea_e378aba119344c6fb1788f45af8b9f17.pdf?index=true
    • https://s3.amazonaws.com/rebesudanolo/23682549359.pdf
    • https://s3.amazonaws.com/vebenok/bill_nye_science_video_worksheets.pdf
    • https://s3.amazonaws.com/jakujakula/what_is_the_best_coffee_maker_with_built_in_grinder.pdf
    • https://4c72699b-aa2e-4dc8-8bd5-1a54e8f938a6.filesusr.com/ugd/f3cb45_e51f39ffaa40410ca23068352352ef47.pdf?index=true
    • https://s3.amazonaws.com/sorogamat/los_pronombres_relativos_en_frances.pdf
    • https://s3.amazonaws.com/vexosafugunu/the_witcher_the_last_wish.pdf
    • https://s3.amazonaws.com/fojaxexino/dipejelojapovusetofe.pdf
    • https://s3.amazonaws.com/suximawo/elements_and_their_symbols_worksheet.pdf
    • https://737c154f-ca75-4484-807d-9d5c19d76377.filesusr.com/ugd/7e84b7_657adfaf2f7f446db34fa086a484966d.pdf?index=true
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f3b7.bin
9f08ca61ca3dfdc2c106142e5b5e5f526d189f99a66c2582a2eb1aefe183e49c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3B7 5264 bytes
font_01_sfnt_off0001058f.bin
7056d104fe750e2c0e6d54cd850d3d3eaef1ba70bd585e0ef8a0bd5447469678
pdf-font-stream PDF embedded font (sfnt) at offset 0x1058F 10744 bytes