Summary
Special template of issue index pattern may cause panic.
Details
in internal/markup/markup.go
link = fmt.Sprintf(`<a href="%s">%s</a>`, com.Expand(metas["format"], metas), m)
Issue index pattern is rendered to link with com.Expand.
However, com.Expand is not safe.
i = strings.Index(template, "}")
if s, ok := match[template[:i]]; ok {when { is found but } not found, i comes to 1, template[:-1] will be called, and then panicked
finally, all pages than contains issue index are unavailable.
PoC
- set issue index pattern as follow
- add a commit which point to an issue in its msg
using #1 above
Impact
DoS that cause part of pages of the specify repo unavailable.
References
Summary
Special template of issue index pattern may cause panic.
Details
in internal/markup/markup.go
Issue index pattern is rendered to link with
com.Expand.However,
com.Expandis not safe.when
{is found but}not found, i comes to 1, template[:-1] will be called, and then panickedfinally, all pages than contains issue index are unavailable.
PoC
using
#1aboveImpact
DoS that cause part of pages of the specify repo unavailable.
References