Malicious PDF — malware analysis report

Static analysis result for SHA-256 9dc0718e926ee3a4…

MALICIOUS

PDF

72.4 KB Created: 2021-04-10 07:08:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: 28273fee2e9115387ca81cb4bdb081c1 SHA-1: 2ef71df6fa10a9c42745873ce61525c17f18f900 SHA-256: 9dc0718e926ee3a41e6776987ae18ec23e677c7c619fb00e10101d4e495b7cc9
126 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many pointing to domains that appear to be part of a link farm or disposable hosting, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of an attempt to redirect users to malicious content.

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://portal-mysigma.com/system/files/student-proof/47432021317.pdf In PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/vonasajevevedatenalezeb.pdfIn PDF document text
    • http://portal-mysigma.com/system/files/student-proof/tevesifisota.pdfIn PDF document text
    • https://vectorcorp.net/sites/default/files/webform/resume/27999686052.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/89533113822.pdfIn PDF document text
    • https://www.mainephilanthropy.org/sites/default/files/79141676299.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/noranixuguwetepefosobad.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/vewamilobofesiwukor.pdfIn PDF document text
    • https://www.visitsavannah.com/sites/default/files/webform/59391310887.pdfIn PDF document text
    • https://www.pharoxglobal.com/sites/default/files/webform/balulata.pdfIn PDF document text
    • http://spotlight-sites.com/sites/default/files/webform/40861703051.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/BkSY9tpko7c/uplcv?utm_term=the+very+busy+spider+story+mapPDF link annotation
    • https://thesanfordschool.asu.edu/sites/default/files/webform/85266863194.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/85064040694.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/putiwokareviwe.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_off0000df19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF19 5420 bytes
SHA-256: 54b551f869b528466682881bcdf57fe1356f1fdd036360ba99e15ef059a42e77
font_01_sfnt_off0000f15c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF15C 10592 bytes
SHA-256: 1d86e0bc9121a139330443bbccde34b1eb79746728878b5198f9b657d095e7f9