Malicious PDF — malware analysis report

Static analysis result for SHA-256 e27dcedbbd7a6357…

MALICIOUS

PDF

72.7 KB Created: 2020-12-08 10:27:05 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2b549f0ba6519cc1404694cf270f79a7 SHA-1: 73c95c72726679d1be85144b58974085e9295765 SHA-256: e27dcedbbd7a6357a1b9fd3f697761ce4d27387ee642f93d9c0ebbc5e2f41e85
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including ClamAV and an ML classifier, as malicious. It contains a large number of embedded external links, a common technique for SEO spam or phishing campaigns. While no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect users to malicious or spam content hosted on external domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://trafffe.ru/strik?utm_term=first+aid+step+1+anki+deck
    • https://cdn-cms.f-static.net/uploads/4379229/normal_5f93a0aa17d92.pdf
    • https://nirulutot.weebly.com/uploads/1/3/4/7/134700174/20c546b3134.pdf
    • https://cdn-cms.f-static.net/uploads/4378390/normal_5f9d027439fee.pdf
    • https://static.s123-cdn-static.com/uploads/4408001/normal_5fc90fc780f79.pdf
    • https://cdn-cms.f-static.net/uploads/4410985/normal_5f9d54afdd9dc.pdf
    • https://mixorone.weebly.com/uploads/1/3/1/4/131438240/6d9f72702a9dd46.pdf
    • https://cdn-cms.f-static.net/uploads/4414175/normal_5fc0f83940e55.pdf
    • https://jazaxalik.weebly.com/uploads/1/3/4/4/134488577/7746192.pdf
    • https://rikurifijuse.weebly.com/uploads/1/3/4/6/134681474/2743582.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/tesotiwapax/nalot.pdf
    • https://s3.amazonaws.com/kawotexulozax/gazegova.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
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cc3b.bin
47668a31b5dc485d3690385843e86950c3ea13f8a3dcb8883998f00bc6bff607
pdf-font-stream PDF embedded font (sfnt) at offset 0xCC3B 5108 bytes
font_01_sfnt_off0000ddb4.bin
bd07c533e9df9f5b5be95a063e862dd61f370d85b0a89932eddd74a0ad8042c0
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDB4 10364 bytes
font_02_sfnt_off00010184.bin
3d50f22d3ae6d9a4461c814f81554cc573a3512c555c2f223aedeeaca19cd658
pdf-font-stream PDF embedded font (sfnt) at offset 0x10184 16080 bytes