Malicious PDF — malware analysis report

Static analysis result for SHA-256 70ddb659836cb6c5…

MALICIOUS

PDF

76.9 KB Created: 2021-05-28 20:16:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 47c07ff6a049be4d87df3f65a26e26e7 SHA-1: 7bf5f7eec4bc0eb04ecd8d2832ae15a5434acf63 SHA-256: 70ddb659836cb6c50b4798eec78769c8da3cbdcf19c549b867b59a3c695f7cce
164 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and a machine learning classifier. It contains a large number of external links, many of which are likely part of a link farm designed to improve SEO for malicious content. One of the primary external links points to a URL that appears to be a lure for exam answer keys, suggesting a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • 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
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://golowaki.ru/123?utm_term=hsslive+model+exam+2019+answer+key
    • https://cdn-cms.f-static.net/uploads/4482228/normal_6041672f70efd.pdf
    • https://jexopagovijum.weebly.com/uploads/1/3/7/5/137518486/kerixetimavusir.pdf
    • https://virukuzababije.weebly.com/uploads/1/3/4/3/134350100/nikup.pdf
    • https://cdn-cms.f-static.net/uploads/4419827/normal_6039f802c3759.pdf
    • https://cdn-cms.f-static.net/uploads/4489852/normal_6050b4571ddb9.pdf
    • https://cdn-cms.f-static.net/uploads/4404755/normal_5fe93e553cdb9.pdf
    • https://cdn-cms.f-static.net/uploads/4393641/normal_606e1412ac16a.pdf
    • https://static.s123-cdn-static.com/uploads/4473637/normal_5fcaa13aa5c22.pdf
    • https://cdn-cms.f-static.net/uploads/4426682/normal_6032f28b78dab.pdf
    • https://nixalimug.weebly.com/uploads/1/3/2/6/132680811/1d914040ee6360.pdf
    • https://cdn-cms.f-static.net/uploads/4481988/normal_5fdc0a944bf1d.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/8a2ad4dd-b5ab-4545-bed3-c9b622ac1cc2/51698043112.pdf
    • https://uploads.strikinglycdn.com/files/459ba3a0-13ec-459b-979e-4865ba309434/funcion_indice_con_coincidir_excel.pdf
    • https://uploads.strikinglycdn.com/files/c5fcdf71-0c3f-45fb-8106-663b842fd37f/17678206930.pdf
    • https://uploads.strikinglycdn.com/files/4e54e59a-fe48-4c21-9cdd-e3eefab7b560/37559990232.pdf
    • https://uploads.strikinglycdn.com/files/805c9ac7-bd6b-4eff-b3c5-cadf01ae1c97/autodesk_autocad_2009_crack_keygen_download.pdf
    • https://uploads.strikinglycdn.com/files/ce2f7ca2-e180-4dd4-b393-be6226df3673/zonabugekuxiguwuxivopox.pdf
    • https://uploads.strikinglycdn.com/files/b553ea61-30d7-4427-a92b-ec66c88a1567/javascript_value_vs_reference_types.pdf
    • https://uploads.strikinglycdn.com/files/7505a5e0-68bc-4230-a567-d225d7c4f734/32817191579.pdf
    • https://uploads.strikinglycdn.com/files/61dfebb3-b40c-46b2-aa7c-f3987c574abd/kadoluvurabewowosigo.pdf
    • https://uploads.strikinglycdn.com/files/09908dd4-5838-4b1e-869b-5c1ee4cc4ad9/what_are_the_zeros_of_a_sine_function.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_off0000ec2b.bin
0628e960aa7c2cd7d25e9c36a13b327a27fe6bc78c2fa1f92d9c31272c4dd0b6
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC2B 5800 bytes
font_01_sfnt_off0000fff0.bin
7aa6df7da37baedb04deb30e44b9f511bb5bc57c34b6ff0d0e024a050d6cde7e
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFF0 11324 bytes