Malicious PDF — malware analysis report

Static analysis result for SHA-256 2cba40a40686220c…

MALICIOUS

PDF

69.0 KB Created: 2021-04-19 23:32:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-30
MD5: 6c0ac7847981d3bb85ccceac010e0637 SHA-1: 9e811cb34557e11f314d3c2aef777cc090a88b46 SHA-256: 2cba40a40686220cc8733e616dce669912b6d460524387650ed81a1adf211e43
126 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to unknown or potentially malicious domains, and is identified as a link farm. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and heuristic firings strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://web.liderpapel.com/sites/default/files/webform/dojoxopanikofogenag.pdf In PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/dizage.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/ranet.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/bidepe.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/zozagosetimof.pdfIn PDF document text
    • https://natsihwa.org.au/sites/default/files/webform/degajakuko.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=characters+in+the+rocking+horse+winnerPDF link annotation
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/65910459182.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/85824103047.pdfIn PDF document text
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/gijewosatesozug.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c6dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6DC 4996 bytes
SHA-256: 455c8514a5067202d66e822e735101b21723a664962c6d48df1d7fa466028b61
font_01_sfnt_off0000d7e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7E3 9756 bytes
SHA-256: 435af9f8c7f4dca26a28b619005bf92be654d4da69df01dc596c3fafb785de4e
font_02_sfnt_off0000f944.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF944 4324 bytes
SHA-256: 7f6049e5011acf0e8581793f2bc2bb947aac2929fdb77abc318b2a6155c1ef71