Malicious PDF — malware analysis report

Static analysis result for SHA-256 0b0d77b05512b02a…

MALICIOUS

PDF

73.9 KB Created: 2020-11-29 02:52:53 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fb549f966bc9d63ed3792ebc94f4b804 SHA-1: cae0258699c653b6168071283fd52019fdd24ef2 SHA-256: 0b0d77b05512b02a766f2bcd52cb2440378ec0c510157ec4ed976c9499ee20d3
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external links, including a link farm heuristic, suggesting it's designed to redirect users to potentially harmful websites. The document body, though heavily obfuscated, contains text related to educational materials, which is likely a lure to disguise the malicious nature of the links.

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-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://trafffi.ru/aws?utm_term=glencoe+algebra+2+answers+page+224
    • https://xabopefasuliwik.weebly.com/uploads/1/3/4/4/134445681/1535284.pdf
    • https://cdn-cms.f-static.net/uploads/4422909/normal_5fa0dd80091ee.pdf
    • https://ravadekivis.weebly.com/uploads/1/3/4/5/134512786/kodomugeje.pdf
    • https://cdn-cms.f-static.net/uploads/4412413/normal_5fc09fbf8eb30.pdf
    • https://cdn-cms.f-static.net/uploads/4369648/normal_5f8c5011bc67b.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/238d58fd-f88b-479a-8632-73d91f8d6d86/maadhaar_app_for_iphone.pdf
    • https://uploads.strikinglycdn.com/files/381ddf2b-b96e-4b87-b10d-1f875250a226/advanced_microeconomic_theory_jehle.pdf
    • https://uploads.strikinglycdn.com/files/de81015d-7769-43a6-af5d-1a2645c57a5b/jopuxarugutegotesopu.pdf
    • https://uploads.strikinglycdn.com/files/63782d7c-6e39-4194-a677-7707618ef1bb/fipivudej.pdf
    • https://uploads.strikinglycdn.com/files/91d63b3f-e362-4c28-a7be-1fac77abf433/dupozovixopuxewujegow.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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off0000ed8f.bin
95a2f00672444adcb65a0cce5df53c735110298208e5b033f7d544efb0cecb88
decompressed-pdf-stream PDF FlateDecoded stream at offset 0xED8F 25720 bytes
font_00_sfnt_off0000b723.bin
cb93fdb75a3ff4a2f8f6b3fee6bc1b2ea31002fd3b77bc93f52fbbd61f6f3306
pdf-font-stream PDF embedded font (sfnt) at offset 0xB723 5584 bytes
font_01_sfnt_off0000ca58.bin
9c1bc6d2de41fdc8636ed50cfb5bbc399c171f287430ca163dd8a579db9ded27
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA58 10220 bytes