Malicious PDF — malware analysis report

Static analysis result for SHA-256 a44a3b5ca9173450…

MALICIOUS

PDF

74.2 KB Created: 2021-01-06 04:40:28 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 4b87cbbc1398e4d963bc1cd26ccb5d78 SHA-1: d7d2400b911154afb4dbf34a62198c5e75d6fd25 SHA-256: a44a3b5ca9173450ac4ed418821f5db0e15904584462b059a37a7430b2f698f1
214 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with one specifically pointing to a known malicious redirector. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though heavily obfuscated, appears to be a lure related to an admission form, suggesting a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://gettraff.ru/aws?utm_term=vydehi+school+of+excellence+admission+form
    • https://cdn-cms.f-static.net/uploads/4366348/normal_5f8b43203862c.pdf
    • https://cdn-cms.f-static.net/uploads/4370560/normal_5f9412a2260ab.pdf
    • https://risegexof.weebly.com/uploads/1/3/4/6/134661868/2329956.pdf
    • https://zupavuzinopaz.weebly.com/uploads/1/3/4/2/134265708/mufojag.pdf
    • https://zikegebuner.weebly.com/uploads/1/3/4/8/134856814/pusin.pdf
    • https://cdn-cms.f-static.net/uploads/4413454/normal_5f94759f644b5.pdf
    • https://sujugixuguxidi.weebly.com/uploads/1/3/4/6/134615921/leweziwigek_nofamurumo_xijufubeximuz_dafasugodo.pdf
    • https://cdn-cms.f-static.net/uploads/4368954/normal_5f92943c8122d.pdf
    • https://cdn-cms.f-static.net/uploads/4478125/normal_5fdc4850338c0.pdf
    • https://zowajapizuxazo.weebly.com/uploads/1/3/0/9/130969341/tovuzarokejowako.pdf
    • https://cdn-cms.f-static.net/uploads/4372377/normal_5f926f80499e5.pdf
    • https://dagakaxogofawi.weebly.com/uploads/1/3/4/6/134699425/a32690168a06.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/ruzaganog/gumugo.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e48c.bin
be2973f9212850b0c1542355f5c676b39763803a19c2dd452f5de232be081f08
pdf-font-stream PDF embedded font (sfnt) at offset 0xE48C 5396 bytes
font_01_sfnt_off0000f6cd.bin
d7747cf3b59f89ed69957e7566b6d81d8da59dabbc08388c0565892d1844591a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6CD 10928 bytes