Http4s: ResourceService and Webjar Service path escape via percent-encoded separators
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 0.23.35, 1.0.0-M47
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: partial
Summary
Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, ResourceService and WebjarService decode each URL path segment but reject only segments exactly equal to an empty string, a dot, or two dots. A request containing percent-encoded slash or backslash separators can turn an accepted segment into a parent-directory traversal after decoding, allowing access to classpath or WebJar resources outside the configured base when a directory-backed classpath is served and the backend preserves the encoded separator. The patch rejects decoded segments containing slash or backslash in ResourceService and WebjarService, and applies the same guard to the non-exploitable FileService for consistency. This issue is fixed in versions 0.23.35 and 1.0.0-M47.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- http4s http4s
fixed in 0.23.35; From 1.0.0-M1 · fixed in 1.0.0-M47
- org.http4s:http4s-server_2.12Maven
fixed in 0.23.35
- org.http4s:http4s-server_2.13Maven
fixed in 0.23.35
- org.http4s:http4s-server_3Maven
fixed in 0.23.35
- org.http4s:http4s-server_3Maven
From 1.0.0-M1 · fixed in 1.0.0-M47
- org.http4s:http4s-server_2.13Maven
From 1.0.0-M1 · fixed in 1.0.0-M47