Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3d9147efc022919…

MALICIOUS

PDF

75.6 KB Created: 2021-04-16 14:53:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 542773ddc97ba8fe5ea3ac35bb537027 SHA-1: 20e5aec0359ed9de81c3b2a2d14949f2e3e71a57 SHA-256: a3d9147efc022919252a0488ae4260eeba1afcc7efc138fcd40907284b5a3477
126 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV as a phishing trojan and a machine learning classifier indicated a high probability of maliciousness. It contains numerous embedded URLs, many of which point to disposable domains or link farms, suggesting a phishing or redirection attempt. The document body, though heavily obfuscated, appears to be a review, likely a lure to entice users to click on the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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.uts.cw/sites/default/files/webform/tidenopuzi.pdf In PDF document text
    • https://ambrose.edu/sites/default/files/webform/20598750849.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/72917344941.pdfIn PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/sakobonomoduriv.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/17232120942.pdfIn PDF document text
    • https://vectorcorp.net/sites/default/files/webform/resume/wogudodijanaferewinige.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/90703453713.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/87762274679.pdfIn PDF document text
    • http://www.pacificsportfraservalley.com/sites/default/files/webform/93322629498.pdfIn PDF document text
    • https://vectorcorp.net/sites/default/files/webform/resume/danodajanenalidadalibebav.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/seliruni.pdfIn PDF document text
    • https://architecturaldesigninc.com/sites/default/files/masugikiretige.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/FevRqgeaUVY/uplcv?utm_term=qsc+gx3+power+amp+reviewPDF link annotation
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/17420147243.pdfIn PDF document text
    • https://ec.europa.eu/eip/agriculture/sites/default/files/webform/27560642257.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_off0000dc64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC64 5268 bytes
SHA-256: 2774f630c49229c238a281a8059324d5db6cd3abfc638abcf9b38026ecbb40d4
font_01_sfnt_off0000ee5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE5C 11012 bytes
SHA-256: c9e3411509c45990eab140dc580174cbcf0d04350b5480d0ace8178a58747d56
font_02_sfnt_off000113d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113D0 4324 bytes
SHA-256: 1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e