CVE-2018-1000005

Description

libcurl 7.49.0 to and including 7.57.0 contains an out bounds read in code handling HTTP/2 trailers. It was reported (https://github.com/curl/curl/pull/2231) that reading an HTTP/2 trailer could mess up future trailers since the stored size was one byte less than required. The problem is that the code that creates HTTP/1-like headers from the HTTP/2 trailer data once appended a string like `:` to the target buffer, while this was recently changed to `: ` (a space was added after the colon) but the following math wasn't updated correspondingly. When accessed, the data is read out of bounds and causes either a crash or that the (too large) data gets passed to client write. This could lead to a denial-of-service situation or an information disclosure if someone has a service that echoes back or uses the trailers for something.

Predictions

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

References

• https://security.archlinux.org/ASA-201801-26
• https://security.archlinux.org/ASA-201801-25
• https://security.archlinux.org/ASA-201801-24
• https://security.archlinux.org/ASA-201801-23
• https://security.archlinux.org/ASA-201801-22
• https://security.archlinux.org/ASA-201801-20
• https://security-tracker.debian.org/tracker/CVE-2018-1000005