Malicious PDF — malware analysis report

Static analysis result for SHA-256 25050722f5ddb7a9…

MALICIOUS

PDF

41.0 KB Created: 2020-03-27 04:17:06 +02:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: 08642307026fd25a6b4f6da8164eeadd SHA-1: b44dd43565475212516c0adaa1e0e3a8547ecc65 SHA-256: 25050722f5ddb7a94a3ed533ecdf0cc4f68d20eca302585cc0bb6c8d19c429ec
94 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document contains a large number of external links, many of which are numerically or generically named, indicating a link farm or SEO manipulation tactic. The ML classifier strongly flagged this PDF as malicious. The document body, though partially corrupted, contains the title 'Ejercicios para balancear ecuaciones por redox' and references the wkhtmltopdf application, suggesting it was generated programmatically to host these links.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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 http://agostomiglia.com/uploads/1/3/1/4/131407592/131407592.html#ejercicios+para+balancear+ecuaciones+por+redox
    • http://reifierentertainmentdevelopment.com/uploads/1/3/0/7/130775977/2421613.pdf
    • http://cordiallyinvited-designs.com/uploads/1/3/0/4/130489051/66964112cba034c.pdf
    • http://forcew.com/uploads/1/3/0/6/130605146/a60282e5d43df3e.pdf
    • http://monsieurcoulibaly.com/uploads/1/3/0/6/130620604/bovagikunevemesajim.pdf
    • http://www.maxiflor.pt/uploads/1/3/0/2/130272442/nilul-tilomuruwigi-zapawazuvesefik-sotutikawinit.pdf
    • http://mgprott.com/uploads/1/3/0/5/130541662/386df11de0fd26.pdf
    • http://www.cierrajayy.com/uploads/1/3/0/6/130605380/2cafb47658.pdf
    • http://adrenalinedrywall.com/uploads/1/3/0/8/130814553/zokojexuto-xojitufiwo-tuminobaduvimas.pdf
    • http://jennaclean.com/uploads/1/3/0/2/130288379/0aefd23.pdf
    • http://coveinnnaplesbay.com/uploads/1/3/0/5/130539427/mumixukome-puvoterafo-godili-fonad.pdf
    • http://enticionote.com/uploads/1/3/0/8/130874059/b0743c022f86c8.pdf
    • http://gozutashoya.com/uploads/1/3/0/8/130874136/mapedajos_gugigofixovelu_poxatiba.pdf
    • http://www.howiholistic.com/uploads/1/3/0/5/130545643/sirobunelojumoj.pdf
    • http://www.canniwi.com/uploads/1/3/0/9/130969627/8ea76503fcd865d.pdf
    • http://tramontanafv.com/uploads/1/3/0/5/130551245/nomegidirot-faraz.pdf
    • http://xiomana.shop/uploads/1/3/0/7/130739348/20baa383d992d.pdf
    • http://admin.graindesigns.co.uk/uploads/1/3/0/5/130540397/343e1a.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/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006b09.bin
3cc92f4cbfd2a124677db7db86ffc8eb47cff6a0b688a68e3cef30bb0004f26d
pdf-font-stream PDF embedded font (sfnt) at offset 0x6B09 8864 bytes
font_01_sfnt_off00008b14.bin
e2f1373bf3d70a40ff4276a486f0a1d2d32154e4f45ad1243a44c3d3b7d91cea
pdf-font-stream PDF embedded font (sfnt) at offset 0x8B14 2652 bytes