Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7df3ee4d6af2f8a…

MALICIOUS

PDF

79.0 KB Created: 2021-04-26 04:20:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: 1bfea07ed96af2d6e0f7b33c005a2d5c SHA-1: 5884ef77495dab91896a4d7e2a52195173b5df07 SHA-256: c7df3ee4d6af2f8a7bd83d1ad76ee7653275db1d4cfe93840e9d4dce4187cc36
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to suspicious domains or appear to be part of a link farm, indicating an attempt to redirect users to malicious content. The document body, though heavily obfuscated, suggests a lure related to 'chess boxing'.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://cicatsalud.com/html/sites/default/files/webform/53132673180.pdf In PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/75468476758.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/dalobasowi.pdfIn PDF document text
    • http://www.birdlifebotswana.org.bw/sites/default/files/webform/sightings-sketches/bikepekeroluxujopabiko.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/koxajupenukolipidawikopi.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/tidenopuzi.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/66890294103.pdfIn PDF document text
    • https://aboss.by/sites/default/files/webform/vobefoxejajizagosoberob.pdfIn PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/jebumimebugamoto.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=who+invented+chess+boxingPDF link annotation
    • https://minorsoncampus.princeton.edu/system/files/webform/zotatati.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/90369837207.pdfIn PDF document text
    • https://gradfutures.princeton.edu/system/files/webform/42179508969.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/piwolumubixu.pdfIn PDF document text
    • https://www.healthdata.org/sites/default/files/resumes/18848190838.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fa42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA42 5144 bytes
SHA-256: b46958f3a97c85899eb231e01878137fce308c37b9a5d2f2e560f90f499359d6
font_01_sfnt_off00010bda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BDA 10468 bytes
SHA-256: e25e9890037b1e48c5b675049fc070b45a8d748c63765a01254a88c52333fec1