Out-of-bounds Read SNYK-DEBIAN8-LIBSSH2-453623
NVD Description
Note: Versions mentioned in the description apply only to the upstream libssh2
package and not the libssh2
package as distributed by Debian
.
See How to fix?
for Debian:8
relevant fixed versions and status.
Vulnerability Overview
The libssh2
library is a popular open-source implementation of the SSH protocol. However, a critical vulnerability was discovered in the libssh2
library, which could allow an attacker to perform an out-of-bounds read. This vulnerability affects versions of libssh2
prior to 1.9.0.
Vulnerability Details
The vulnerability is caused by an integer overflow in the kex_method_diffie_hellman_group_exchange_sha256_key_exchange
function in the kex.c
file. This function is responsible for handling the Diffie-Hellman key exchange protocol, which is a critical component of the SSH protocol.
When an attacker sends a malicious packet to the server, the kex_method_diffie_hellman_group_exchange_sha256_key_exchange
function can overflow the buffer, leading to an out-of-bounds read. This can allow the attacker to disclose sensitive information or cause a denial-of-service condition on the client system.
Remediation
To remediate this vulnerability, it is essential to upgrade the libssh2
library to version 1.4.3-4.1+deb8u4 or higher. This will ensure that the vulnerable function is patched, and the out-of-bounds read vulnerability is mitigated.
References
- https://security-tracker.debian.org/tracker/CVE-2019-13115
- https://security.netapp.com/advisory/ntap-20190806-0002/
- https://support.f5.com/csp/article/K13322484
- https://support.f5.com/csp/article/K13322484?utm_source=f5support&utm_medium=RSS
- https://lists.debian.org/debian-lts-announce/2019/07/msg00024.html
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/6LUNHPW64IGCASZ4JQ2J5KDXNZN53DWW/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/M7IF3LNHOA75O4WZWIHJLIRMA5LJUED3/
- https://github.com/libssh2/libssh2/compare/02ecf17...42d37aa
- https://github.com/libssh2/libssh2/pull/350
- https://blog.semmle.com/libssh2-integer-overflow/
- https://libssh2.org/changes.html
- https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b@%3Cissues.bookkeeper.apache.org%3E
- https://lists.apache.org/thread/html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4@%3Cissues.bookkeeper.apache.org%3E
- http://people.ubuntu.com/~ubuntu-security/cve/CVE-2019-13115
- http://packetstormsecurity.com/files/172834/libssh2-1.8.2-Out-Of-Bounds-Read.html
- https://lists.apache.org/thread/html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b@%3Cissues.bookkeeper.apache.org%3E
- https://lists.apache.org/thread/html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4@%3Cissues.bookkeeper.apache.org%3E
- https://lists.debian.org/debian-lts-announce/2021/12/msg00013.html
- https://lists.debian.org/debian-lts-announce/2023/09/msg00006.html
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/6LUNHPW64IGCASZ4JQ2J5KDXNZN53DWW/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/M7IF3LNHOA75O4WZWIHJLIRMA5LJUED3/
- https://support.f5.com/csp/article/K13322484?utm_source=f5support&utm_medium=RSS
Impact
The out-of-bounds read vulnerability in the libssh2
library can have significant consequences for users of the library. An attacker who exploits this vulnerability can potentially disclose sensitive information or cause a denial-of-service condition on the client system.
Mitigation
To mitigate this vulnerability, it is essential to upgrade the libssh2
library to version 1.4.3-4.1+deb8u4 or higher. This will ensure that the vulnerable function is patched, and the out-of-bounds read vulnerability is mitigated.
Conclusion
The out-of-bounds read vulnerability in the libssh2
library is a critical issue that requires immediate attention. Users of the library should upgrade to the latest version to ensure that their systems are secure.
Q: What is the out-of-bounds read vulnerability in the libssh2
library?
A: The out-of-bounds read vulnerability in the libssh2
library is a critical issue that allows an attacker to perform an out-of-bounds read. This vulnerability affects versions of libssh2
prior to 1.9.0.
Q: What is the impact of this vulnerability?
A: The out-of-bounds read vulnerability in the libssh2
library can have significant consequences for users of the library. An attacker who exploits this vulnerability can potentially disclose sensitive information or cause a denial-of-service condition on the client system.
Q: How can I determine if my system is affected by this vulnerability?
A: To determine if your system is affected by this vulnerability, you can check the version of the libssh2
library installed on your system. If the version is prior to 1.9.0, your system is likely affected.
Q: What is the recommended mitigation for this vulnerability?
A: The recommended mitigation for this vulnerability is to upgrade the libssh2
library to version 1.4.3-4.1+deb8u4 or higher. This will ensure that the vulnerable function is patched, and the out-of-bounds read vulnerability is mitigated.
Q: Can I patch the vulnerable function myself?
A: It is not recommended to patch the vulnerable function yourself. The patch is a complex change that requires a deep understanding of the libssh2
library and its codebase. It is recommended to upgrade to the latest version of the library, which includes the patch.
Q: Are there any other vulnerabilities in the libssh2
library that I should be aware of?
A: Yes, there are other vulnerabilities in the libssh2
library that you should be aware of. It is essential to regularly check for updates and patches to ensure that your system is secure.
Q: Can I use the libssh2
library in production without patching the vulnerability?
A: No, it is not recommended to use the libssh2
library in production without patching the vulnerability. The out-of-bounds read vulnerability is a critical issue that can have significant consequences for users of the library.
Q: How can I stay informed about security updates and patches for the libssh2
library?
A: You can stay informed about security updates and patches for the libssh2
library by regularly checking the official website of the library, as well as security mailing lists and blogs.
Q: Can I use a different SSH library instead of libssh2
?
A: Yes, you can use a different SSH library instead of libssh2
. However, it is essential to ensure that the new library is secure and has not been affected by similar vulnerabilities.
Q: How can I report a vulnerability in the libssh2
library?
A: You can report a vulnerability in the libssh2
library by sending an email to the library's maintainers or by submitting a bug report through the library's issue tracker.
Q: What is the timeline for patching the out-of-bounds read vulnerability in the libssh2
library?
A: The timeline for patching the out-of-bounds read vulnerability in the libssh2
library is dependent on the library's maintainers and the complexity of the patch. It is essential to regularly check for updates and patches to ensure that your system is secure.