Auth bypass in Libssh
CVE-2023-2283
A vulnerability was found in libssh, where the authentication check of the connecting client can be bypassed in the`pki_verify_data_signature` function in memory allocation problems. This issue may happen if there is insufficient memory or the memory usage is limited. The problem is caused by the return value `rc,` which is initialized to SSH_ERROR and later rewritten to save the return value of the function call `pki_key_check_hash_compatible.` The value of the variable is not changed between this point and the cryptographic verification. Therefore any error between them calls `goto error` returning SSH_OK.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.011 (63.2th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 63rd percentile — 63.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000
Affected products
- Libssh
- Fedoraproject Fedora — versions 37
- Red Hat Enterprise Linux — versions 8.0, 9.0
- Libssh — versions libssh-2
Weakness classification (CWE)
Public proof-of-concept exploits
References
- access.redhat.com/security/cve/CVE-2023-2283 (Third Party Advisory)
- www.libssh.org/security/advisories/CVE-2023-2283.txt (Vendor Advisory)
- bugzilla.redhat.com/show_bug.cgi (Third Party Advisory, Issue Tracking)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- packetstormsecurity.com/files/172861/libssh-0.9.6-0.10.4-pki_verify_data_signat…
- security.gentoo.org/glsa/202312-05 (vendor-advisory)
- security.netapp.com/advisory/ntap-20240201-0005/
- af854a3a-2127-422b-91ae-364da2661108
Frequently asked questions
- What is CVE-2023-2283?
- CVE-2023-2283 is a medium-severity vulnerability in Libssh, classified under Improper Authentication. CVSS score: 6.5/10. Published 2023-05-26.
- How severe is CVE-2023-2283?
- Medium severity. CVSS v3 base score is 6.5 out of 10.
- Is CVE-2023-2283 known to be exploited?
- 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.