Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a858bcf2fefa0ee…

MALICIOUS

PDF

69.6 KB Created: 2021-02-24 11:17:42 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 623e3a2989e14bca96104997405480c0 SHA-1: 33eaaa3b8bd07183084dc41f23b3068354684b75 SHA-256: 7a858bcf2fefa0ee0e07613234d252736542108613190b5c4f55516a8fd90e30
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The file contains a large number of external links, many pointing to PDF files hosted on various domains, suggesting a link farm or a distribution mechanism for further malicious content. The document body is heavily obfuscated and contains what appears to be metadata from the wkhtmltopdf tool.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://seumenha.ru/wix?keyword=medicare+benefit+policy+manual+chapter+6+section+20.5.2+and+20.7
    • http://italiabeach.space/inconel_600_sheet_supplierst6tgs.pdf
    • https://static.s123-cdn-static.com/uploads/4475988/normal_6000842becc4c.pdf
    • https://jesidovelagira.weebly.com/uploads/1/3/4/7/134705211/8356996.pdf
    • https://static.s123-cdn-static.com/uploads/4387932/normal_5fc753b59dee4.pdf
    • https://setibadumizokeg.weebly.com/uploads/1/3/4/8/134880372/d7feae0d.pdf
    • https://jekugisolidib.weebly.com/uploads/1/3/4/0/134097103/19496518e.pdf
    • http://hdvideo.design/26485688435qulyi.pdf
    • https://sifegofariwe.weebly.com/uploads/1/3/1/4/131437131/waxamax-xalisapizuneb.pdf
    • http://doorstepcomputers.com/tsum_coin_farming_chartq1kwx.pdf
    • https://newogofifexepe.weebly.com/uploads/1/3/4/8/134884114/615269.pdf
    • http://suzuxef.22web.org/bootstrap_form_search_button.pdf
    • https://sobemifukoku.weebly.com/uploads/1/3/4/8/134887972/gepujoretefoli_xogamizevutora_fugonoradukobir_gexufo.pdf
    • https://cdn-cms.f-static.net/uploads/4450864/normal_60313e28e2672.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://tizafuj.epizy.com/dell_latitude_e6430_wireless_driver_windows_7_32_bit.pdf
    • 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_off0000d1d7.bin
8a9c40a6222b9747987714e8c2e6e59612aad09a9c61aa0c17a133a9a072caec
pdf-font-stream PDF embedded font (sfnt) at offset 0xD1D7 6308 bytes
font_01_sfnt_off0000e742.bin
967dbb10c632af19cc977dff2829f2ceb2a5429ca61501e42a39868364ca9bdf
pdf-font-stream PDF embedded font (sfnt) at offset 0xE742 9928 bytes