When doing a TFTP transfer and curl/libcurl is given a URL that contains a very long file name (longer than about 515 bytes), the file name is truncated to fit within the buffer boundaries, but the buffer size is still wrongly updated to use the untruncated length. This too large value is then used in the sendto() call, making curl attempt to send more data than what is actually put into the buffer. The endto() function will then read beyond the end of the heap based buffer. A malicious HTTP(S) server could redirect a vulnerable libcurl-using client to a crafted TFTP URL (if the client hasn't restricted which protocols it allows redirects to) and trick it to send private memory contents to a remote server over UDP. Limit curl's redirect protocols with --proto-redir and libcurl's with CURLOPT_REDIR_PROTOCOLS.
The MITRE CVE dictionary describes this issue as:
Find out more about CVE-2017-1000100 from the MITRE CVE dictionary dictionary and NIST NVD.
Red Hat Product Security has rated this issue as having Low security impact. This issue is not currently planned to be addressed in future updates. For additional information, refer to the Issue Severity Classification: https://access.redhat.com/security/updates/classification/.
CVSS3 Base Score | 4.8 |
---|---|
CVSS3 Base Metrics | CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L |
Attack Vector | Network |
Attack Complexity | High |
Privileges Required | None |
User Interaction | None |
Scope | Unchanged |
Confidentiality | Low |
Integrity Impact | None |
Availability Impact | Low |
Platform | Errata | Release Date |
---|---|---|
Red Hat Software Collections for Red Hat Enterprise Linux 6 (httpd24-curl) | RHSA-2018:3558 | 2018-11-13 |
Red Hat Software Collections for Red Hat Enterprise Linux 7 (httpd24-curl) | RHSA-2018:3558 | 2018-11-13 |
Platform | Package | State |
---|---|---|
Red Hat JBoss Web Server 3.0 | curl | Will not fix |
Red Hat Enterprise Linux 7 | curl | Will not fix |
Red Hat Enterprise Linux 6 | curl | Will not fix |
Red Hat Enterprise Linux 5 | curl | Will not fix |
Red Hat Ceph Storage 2 | curl | Will not fix |
RHEV Manager 3 | mingw-virt-viewer | Will not fix |
.NET Core 2.0 on Red Hat Enterprise Linux | rh-dotnet20-curl | Affected |
.NET Core 2.0 on Red Hat Enterprise Linux | rh-dotnet21-curl | Affected |
.NET Core 1.0 on Red Hat Enterprise Linux | rh-dotnetcore10-curl | Affected |
.NET Core 1.0 on Red Hat Enterprise Linux | rh-dotnetcore11-curl | Affected |