Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b83a8bde689f521…

MALICIOUS

PDF

35.2 KB Created: 2020-09-17 03:19:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cf1699780763e3ba61fe6f9fe763930a SHA-1: e375133eed465c7c6bcc8ca7b3fc57f0d5071aec SHA-256: 6b83a8bde689f5212d373119a6e80bc408e9bd552f8b29cf1be06420d9d427dc
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, with one specifically pointing to a known malicious redirector. The heuristic 'PDF_SEO_LINK_FARM' indicates a large number of external PDF links, suggesting a link farm designed to distribute malicious content or facilitate phishing. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://ttraff.club/wix?keyword=reader%2527s+digest+music+books+pdf
    • http://katus.deliverydoula.com/uploads/1/3/1/3/131383483/gazurebafel-gowujiremezogo.pdf
    • http://files.nuttyhistory.com/uploads/1/3/0/7/130738637/1067038.pdf
    • http://rimexeput.almosthomecare.com/uploads/1/3/2/7/132741066/rawutenofuvowag-xojuxed-zobekawogaju-duxokulipix.pdf
    • http://sazixudel.derwenttrees.com/uploads/1/3/1/1/131164462/gapuzikif.pdf
    • http://tekudiwak.idahobluegrassassociation.org/uploads/1/3/2/6/132695517/popuvekot.pdf
    • http://files.lneconstruction.com/uploads/1/3/2/6/132681368/008b7e8f69cf.pdf
    • http://turuxob.mgss.com/uploads/1/3/0/7/130739344/dabagadogifovodip.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://4af72dcd-994d-445d-97c0-e8c823f0f3e5.filesusr.com/ugd/f2c1dc_2de9953324af4914a4665156502ee51d.pdf?index=true
    • https://8e04d384-1c71-4eef-9c80-f24cd143a50e.filesusr.com/ugd/238140_29984eb4384748b6b5764ae31f81bb0c.pdf?index=true
    • https://6384adf7-2cd7-46df-9afb-a79356f838dd.filesusr.com/ugd/2994dd_7cd72d3f3bf241f1af0ef3478f9dd72b.pdf?index=true
    • https://3d4e58da-5e0d-474d-83f3-1286cfee71a1.filesusr.com/ugd/e3ff21_6e8b2b8a73a141aa8ada06e039d69eb0.pdf?index=true
    • 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_off00004ae7.bin
8d801b91318ee6ca6256c25fb2f5435f359db8be167d897646e0a2b6092112aa
pdf-font-stream PDF embedded font (sfnt) at offset 0x4AE7 5688 bytes
font_01_sfnt_off00005e46.bin
4ff42736058f823c9f07afaca17abc465c4ff393d37041dec0e307f792a18438
pdf-font-stream PDF embedded font (sfnt) at offset 0x5E46 9968 bytes