Bug 1766898 (CVE-2019-17498)
| Summary: | CVE-2019-17498 libssh2: integer overflow in SSH_MSG_DISCONNECT logic in packet.c | ||
|---|---|---|---|
| Product: | [Other] Security Response | Reporter: | Dhananjay Arunesh <darunesh> |
| Component: | vulnerability | Assignee: | Red Hat Product Security <security-response-team> |
| Status: | CLOSED ERRATA | QA Contact: | |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | unspecified | CC: | djuran, erik-fedora, fidencio, kdudka, marcandre.lureau, mike, paul, rjones |
| Target Milestone: | --- | Keywords: | Security |
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | If docs needed, set a value | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2020-09-29 21:58:46 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
| Bug Depends On: | 1766903, 1766904, 1766905, 1767506, 1767507, 1767508 | ||
| Bug Blocks: | 1766902 | ||
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Description
Dhananjay Arunesh
2019-10-30 09:03:21 UTC
Created libssh2 tracking bugs for this issue: Affects: fedora-all [bug 1766903] Created mingw-libssh2 tracking bugs for this issue: Affects: fedora-all [bug 1766904] Created mingw-libssh2 tracking bugs for this issue: Affects: epel-7 [bug 1766905] upstream commit: https://github.com/libssh2/libssh2/commit/dedcbd10 External References: https://blog.semmle.com/libssh2-integer-overflow-CVE-2019-17498/ Analysis: This flaw needs a malicious MITM SSH server. When an application compiled with libssh2 connects to such a MITM SSH server, the server can trigger an integer overflow leading to an OOB read in the SSH_MSG_DISCONNECT logic. This can cause the application compiled with libssh2 to crash. This is strictly a client side crash and the SSH server may not be affected. Regarding "remote information disclosure" mentioned in https://blog.semmle.com/libssh2-integer-overflow-CVE-2019-17498/ , if the user connects to a malicious MITM server there is already a risk of disclosing password/keys irrespective of the flaw. Statement: This flaw needs a malicious MITM SSH server. When an application compiled with libssh2 connects to such a MITM SSH server, the server can trigger an integer overflow leading to an OOB read in the SSH_MSG_DISCONNECT logic. This can cause the application compiled with libssh2 to crash. This is strictly a client side crash and the SSH server may not be affected. Also note that when a user connects to a malicious MITM server there is already a risk of disclosing password/keys irrespective of the flaw. This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Via RHSA-2020:3915 https://access.redhat.com/errata/RHSA-2020:3915 This bug is now closed. Further updates for individual products will be reflected on the CVE page(s): https://access.redhat.com/security/cve/cve-2019-17498 |