Malicious PDF — malware analysis report

Static analysis result for SHA-256 42a1fdcd97250371…

MALICIOUS

PDF

77.0 KB Created: 2021-03-21 01:57:31 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 20f4ab9e5433c38296e79a678fda2a5c SHA-1: 212e417c26529df8d598788acd9a89699ff5476e SHA-256: 42a1fdcd9725037109ec9bdc6900691c1aaf91b8e09be5800f54fffbe4a02393
156 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to other PDF files, suggesting a link farm or SEO abuse for malicious purposes. The ClamAV detection and ML classifier strongly indicate maliciousness. The embedded URLs are likely used to redirect users to malicious websites, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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
  • 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://druttle.ru/award?keyword=industrial+and+organizational+psychology+journal+pdf
    • https://cdn-cms.f-static.net/uploads/4466366/normal_60416586b26d5.pdf
    • http://kefijor.mygamesonline.org/articles_on_higher_education_in_pakistan.pdf
    • http://uorott.com/what_is_the_setting_of_act_3_why_is_that_importantucip1.pdf
    • https://vabuxijipureg.weebly.com/uploads/1/3/4/4/134476882/xegunobimufufuja.pdf
    • http://vanimerukaguto.scienceontheweb.net/rijuxufofa.pdf
    • http://7lessons.space/romeo_and_juliet_act_3_scene_1_extract_questiony6y9o.pdf
    • https://cdn-cms.f-static.net/uploads/4393361/normal_5fd7b79a48c23.pdf
    • http://marketeuro.pro/sword_art_online_ps_vita_games_in_orderhgqgx.pdf
    • https://static.s123-cdn-static.com/uploads/4374021/normal_5ff078e3c2af6.pdf
    • https://cdn-cms.f-static.net/uploads/4369655/normal_6031043d61b8a.pdf
    • https://kikuvabafot.weebly.com/uploads/1/3/4/3/134332304/1759726.pdf
    • https://xifofenanupov.weebly.com/uploads/1/3/4/8/134857182/vimanilikotuvopuvu.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/tidigudetefumof/povemumuxusulajepuf.pdf
    • https://s3.amazonaws.com/panokojol/54158712667.pdf
    • http://rojanesifilagu.myartsonline.com/hypothetico_deductive_method.pdf
    • https://s3.amazonaws.com/nijosinizo/68579399821.pdf
    • https://s3.amazonaws.com/woberiz/5606282119.pdf
    • https://s3.amazonaws.com/fuzafuzeruwit/39854553632.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_off0000ed11.bin
83b88168a080e9219d04a6b086a290a1e1f3a3daebef0cfa17ce37230e38d963
pdf-font-stream PDF embedded font (sfnt) at offset 0xED11 5580 bytes
font_01_sfnt_off0001001e.bin
eb7a96919e7f27f0a34e783a4fd9daba53de404d749a2361a15e8092fda1bf67
pdf-font-stream PDF embedded font (sfnt) at offset 0x1001E 11416 bytes