Malicious PDF — malware analysis report

Static analysis result for SHA-256 99a84c9b272a3141…

MALICIOUS

PDF

68.7 KB Created: 2021-01-24 13:11:56 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 67eef5245a8772496ca97fd923f33e97 SHA-1: 703498120832f5c66e12bfba8ec509fd248355e7 SHA-256: 99a84c9b272a31418bb619616b78d605fe773bb4ad85bd67831f936548f1f6cd
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, identified by the 'PDF_SEO_LINK_FARM' heuristic, suggesting a link farm or phishing attempt. The ClamAV detection and ML classifier also indicate malicious content. While no scripts were explicitly extracted, the presence of embedded URLs and the overall structure point towards a malicious document designed to redirect users to potentially harmful sites.

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 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.
  • 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://leonvi.ru/aws?utm_term=writing+linear+equations+from+tables+worksheet PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4382621/normal_5ff7ee0c7e2b1.pdfIn PDF document text
    • http://wokelegekak.66ghz.com/45274746278.pdfIn PDF document text
    • http://opsnatur.fun/20089802594czik5.pdfIn PDF document text
    • https://teribupugabi.weebly.com/uploads/1/3/4/8/134852699/fibiputisitumiw.pdfIn PDF document text
    • http://tameenegypt.com/mamepetojuwanojudutagiwrkhj.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4456660/normal_60006c455fc39.pdfIn PDF document text
    • http://save50.pro/vocabulary_workshop_level_b8ogr6.pdfIn PDF document text
    • https://funujitumim.weebly.com/uploads/1/3/5/3/135347265/bumewudorexe.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4408721/normal_5fdd9d0d9e985.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4462678/normal_5fe1a699f4114.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://posugez.epizy.com/xetawajedegexifaxizo.pdfIn PDF document text
    • http://borinalujid.epizy.com/lifixolemero.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_off0000cf8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF8B 5616 bytes
SHA-256: fa08f9104977bd96042e6f0de0cafffc503373e3c2deaf19865619c858ef071c
font_01_sfnt_off0000e298.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE298 10360 bytes
SHA-256: 5ef4f7d8ee45705830fd2138ea399fc15c7f53e02c155da904c0d38b7292206f