Oh, it looks like that. I can see the same errors from the system log:
java.lang.IndexOutOfBoundsException
at hudson.MarkupText.rangeCheck(MarkupText.java:276)
at hudson.MarkupText.addMarkup(MarkupText.java:270)
at hudson.plugins.ansicolor.ColorConsoleAnnotator$1EmitterImpl.emitHtml(ColorConsoleAnnotator.java:74)
at hudson.plugins.ansicolor.AnsiAttributeElement.emitClose(AnsiAttributeElement.java:42)
at hudson.plugins.ansicolor.AnsiHtmlOutputStream.closeOpenTags(AnsiHtmlOutputStream.java:107)
at hudson.plugins.ansicolor.AnsiHtmlOutputStream.processAttributeRest(AnsiHtmlOutputStream.java:542)
at hudson.plugins.ansicolor.AnsiOutputStream.processEscapeCommand(AnsiOutputStream.java:358)
...