Malicious PDF — malware analysis report

Static analysis result for SHA-256 a49be1097f843ecc…

MALICIOUS

PDF

76.0 KB Created: 2021-04-22 15:18:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: ed0ea93fa9a36421a5f8a35ebf6681fd SHA-1: ddd653c7d8b89705733ec6fee97d6cbf315f64a2 SHA-256: a49be1097f843ecc2f7600df6350a14f1d9e904684ec546d8d9afeae4b47acbb
126 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of numerous external URIs, many pointing to potentially disposable domains, suggests a link farm or phishing operation. Although no scripts were explicitly extracted, the PDF structure and heuristic firings point towards a malicious document designed to deceive users, likely as a precursor to further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://www.termis.org/system/files/webform/dexifivoneput.pdf In PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/sojivezogi.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/doxuwekuwazomiloxeri.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/nolukaronedibikix.pdfIn PDF document text
    • http://russian-ice-spb.ru/sites/default/files/webform/files/32020734574.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/tatemomolefifepa.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/32056102714.pdfIn PDF document text
    • https://europa-ts.ru/sites/default/files/webform/sujeludepotunebimetoravij.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/xubapubawaral.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.opentle.orgIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=dji+naza+m+lite+configurationPDF link annotation
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/17420147243.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/nexeginexepor.pdfIn PDF document text
    • https://minorsoncampus.princeton.edu/system/files/webform/janoruzafasolefixos.pdfIn PDF document text
    • https://thesanfordschool.asu.edu/sites/default/files/webform/83703622856.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
    • http://www.gnu.org/licenses/gpl.htmlIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cf57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF57 5032 bytes
SHA-256: 4fbf6406abad7343813f1083628f1e65e1a8b468d82b60d1d7c986650f3dd5e6
font_01_sfnt_off0000e05b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE05B 6068 bytes
SHA-256: d2d10b6b0c668cf26faa9347c7054f8580c7eefa5cb7aecda2a4fba74bd025f0
font_02_sfnt_off0000f00c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF00C 11296 bytes
SHA-256: d15a06d2c82a9b8f438c02ca26c3a9e9c565e20c0430c0c93f40115e4f96b55d
font_03_sfnt_off00011589.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11589 4324 bytes
SHA-256: 1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e