FreeBSD VuXML: Documenting security issues in FreeBSD and the FreeBSD Ports Collection

cURL -- out of bounds read

Affected packages
7.20 <= curl < 7.56.1

Details

VuXML ID 143ec3d6-b7cf-11e7-ac58-b499baebfeaf
Discovery 2017-10-23
Entry 2017-10-23

The cURL project reports:

libcurl contains a buffer overrun flaw in the IMAP handler.
An IMAP FETCH response line indicates the size of the returned data, in number of bytes. When that response says the data is zero bytes, libcurl would pass on that (non-existing) data with a pointer and the size (zero) to the deliver-data function.
libcurl's deliver-data function treats zero as a magic number and invokes strlen() on the data to figure out the length. The strlen() is called on a heap based buffer that might not be zero terminated so libcurl might read beyond the end of it into whatever memory lies after (or just crash) and then deliver that to the application as if it was actually downloaded.

References

CVE Name CVE-2017-1000257
URL https://curl.haxx.se/docs/adv_20171023.html