Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb654a850bdd6a1f…

MALICIOUS

PDF

47.5 KB Created: 2020-03-20 03:22:15 +02:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: 0bcd642f5dc9c4507eb3c7c6a6ae964b SHA-1: 0e2726d0e8fc67b1f4465dcded2da3c9e6240977 SHA-256: cb654a850bdd6a1fd12702aeb349018a836fc842cc85f39c3fba3e7f9c4eccc6
94 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to SEO-optimized PDF files on unrelated domains. This suggests a link farm or redirection scheme designed to distribute malicious content or traffic. The ML classifier strongly supports the malicious nature of this PDF. No scripts were extracted, and the document body is heavily obfuscated.

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://cakesandcandids.com/uploads/1/3/0/7/130775228/130775228.html#canciones+en+ingles+para+ni%C3%B1os+de+primaria+con+letra
    • http://greenlandhealthcaregroup.com/uploads/1/3/0/4/130490476/5122085.pdf
    • http://sainttheresacatholicchurch.com/uploads/1/3/0/5/130588922/mesosegivoparupip.pdf
    • http://drjhbahena.com/uploads/1/3/0/5/130543169/4b896c47ca584c.pdf
    • http://eleanorsnowandrews.com/uploads/1/3/0/5/130588463/pajofake_lukovizopamakux.pdf
    • http://thecivilreview.com/uploads/1/3/0/5/130588676/5431128.pdf
    • http://www.gracesportfolio.co.uk/uploads/1/3/0/5/130551212/tetedomowupaki.pdf
    • http://gandsplumbingwekeepyourpipesflowing.com/uploads/1/3/0/5/130551935/5753044.pdf
    • http://ar-autodetailing.com/uploads/1/3/0/4/130490006/pikofavojawof_botit.pdf
    • http://summit2summitcoaching.com/uploads/1/3/0/5/130540046/kamajenib.pdf
    • http://clearstonewealth.sydney/uploads/1/3/0/6/130639266/sedarezesilirepe.pdf
    • http://www.corkageldn.com/uploads/1/3/0/5/130589239/2b7fec7fa4.pdf
    • http://www.kathybacongreenberg.com/uploads/1/3/0/2/130274319/8093331.pdf
    • http://fantasiabysimoni.com/uploads/1/3/0/3/130313524/e7b6a6d42fd.pdf
    • http://plays.holyrood-drama.com/uploads/1/3/0/5/130588246/4818584.pdf
    • http://arobalsam.us/uploads/1/3/0/9/130969266/7159583.pdf
    • http://simpsonparkyouth.com/uploads/1/3/0/4/130436258/8716390605f5fa.pdf
    • http://mta-sts.mx.noahsartdesigns.com/uploads/1/3/0/5/130551556/1754306.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_off0000761e.bin
ff7efbf3b04d9bfd5853e3d61e48e5bc25238c9a570842c34da39ac2c63cb042
pdf-font-stream PDF embedded font (sfnt) at offset 0x761E 9264 bytes
font_01_sfnt_off000097ac.bin
1d1fa5121415f8f5353993473374918b9d2a38f433752094af4cce5d3be72c8c
pdf-font-stream PDF embedded font (sfnt) at offset 0x97AC 16312 bytes