Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3955a5ffb6f47e4…

MALICIOUS

PDF

63.6 KB Created: 2020-11-20 07:57:41 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 33bbe72aed428c5f8d9fade150d3c08d SHA-1: c91da58e3aa6c076dae58f345f9240a9de306b06 SHA-256: b3955a5ffb6f47e438f1d30c840c6163620d836f129fa0d7e4f3a43a46dc5028
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, with a critical heuristic identifying a link farm pointing to other PDFs. One of these links, 'https://trafffe.ru/aws?utm_term=square+root+of+169+in+simplest+form', is directly embedded in the document's content, suggesting a phishing or scam attempt. ClamAV detection and ML classification further support its malicious nature, classifying it as a phishing trojan.

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://trafffe.ru/aws?utm_term=square+root+of+169+in+simplest+form
    • https://xikewewojan.weebly.com/uploads/1/3/4/0/134095915/4513207.pdf
    • https://varemajog.weebly.com/uploads/1/3/4/5/134585454/a8a6efc56a0a4.pdf
    • https://galixasuja.weebly.com/uploads/1/3/4/5/134518214/5b2339.pdf
    • https://cdn-cms.f-static.net/uploads/4413575/normal_5f9a873c7f034.pdf
    • https://bizetuxerupa.weebly.com/uploads/1/3/0/8/130873791/zogunulipikasajakugo.pdf
    • https://sidugavumudoriz.weebly.com/uploads/1/3/4/9/134902227/samozadifalibusi.pdf
    • https://vebifejelib.weebly.com/uploads/1/3/0/7/130775119/limagunula.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/jedaxopopuko/suvedakiboviwuxe.pdf
    • https://s3.amazonaws.com/susopuzupure/fofaviwudademenupuwiva.pdf
    • https://uploads.strikinglycdn.com/files/fdbe35c4-dffb-466e-8158-ff533e3f680a/41830113424.pdf
    • https://s3.amazonaws.com/vuforewebub/how_tall_are_hurdles_in_olympics.pdf
    • https://uploads.strikinglycdn.com/files/6da58f3d-a2d7-4603-a8e5-31344652d119/kotor_jedi_leveling_guide.pdf
    • https://s3.amazonaws.com/pazifetanegapu/74709586439.pdf
    • https://uploads.strikinglycdn.com/files/d70bcc68-b62e-4103-b903-16532036725e/96041962858.pdf
    • https://s3.amazonaws.com/leteraxewe/mosoti.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_off0000bbd5.bin
a45f9036e1ed6aa03cac14af2899b622eddef2274262abebda281c7707cc0db7
pdf-font-stream PDF embedded font (sfnt) at offset 0xBBD5 5636 bytes
font_01_sfnt_off0000cef6.bin
688940a058fb28a59de9217a59d487a9c838b9d664f137850a106e69e59e92ec
pdf-font-stream PDF embedded font (sfnt) at offset 0xCEF6 10092 bytes