Malicious PDF — malware analysis report

Static analysis result for SHA-256 54430b4ac9a81320…

MALICIOUS

PDF

71.7 KB Created: 2021-04-10 09:08:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: cc78f4f8f3f0494880b1e3e2b729cb7e SHA-1: 1fb061013a1d6b3275decce9b5d13eb22990dc19 SHA-256: 54430b4ac9a81320f8820e91a397d1f6398a5ddde3f546155989a747c46b70b9
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to domains that appear to be part of a link farm, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.a1touchsolution.nl/sites/default/files/73086307569.pdf In PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/setafemamuf.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/22559513310.pdfIn PDF document text
    • https://extranet.blanchisserie-toulousaine-de-sante.com/sites/extranet.blanchisserie-toulousaine-de-sante.com/files/documents/justificatifs/bugoxugokerudanetisene.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/11118021720.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/subeditanutojodojewogize.pdfIn PDF document text
    • https://www.mainephilanthropy.org/sites/default/files/50588642306.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/60015669747.pdfIn PDF document text
    • http://www.pacificsportfraservalley.com/sites/default/files/webform/joxelivoresilawefuxeli.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/monufugabezexi.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/koxajupenukolipidawikopi.pdfIn PDF document text
    • https://www.jsif.org/sites/default/files/webform/vinuriruxelapaviwona.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/22206840813.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/vonasajevevedatenalezeb.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/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=labeled+parts+of+a+circlePDF link annotation
    • https://minorsoncampus.princeton.edu/system/files/webform/posilo.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/jidubiziro.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_off0000d9cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9CD 5228 bytes
SHA-256: 52ba79a77bfa2a4d6f706447d6f4461ac2b863503b6e45aa94f88cc620a8e9cd
font_01_sfnt_off0000eba2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBA2 10864 bytes
SHA-256: 1ea1042b64b28869007f1d127f45873ae9406ebd292fe25b8c91c65898fcf1df