CVE-2018-1000005

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.

From the Ubuntu Security Team

leosilva> vulnerability code was introduced after version 7.47 leosilva> trusty and precise/esm are not-affected.

• How can I get the fixes?
• What do statuses mean?
• Patch details

References

• MITRE
• NVD
• Launchpad
• Debian

Related Ubuntu Security Notices (USN)

• USN-3554-1
• curl vulnerabilities
• 31 January 2018

Other references

• https://github.com/curl/curl/pull/2231
• https://curl.haxx.se/docs/adv_2018-824a.html
• https://www.cve.org/CVERecord?id=CVE-2018-1000005