CVE-2025-5987
Libssh: invalid return code for chacha20 poly1305 with openssl backend
Description
A flaw was found in libssh when using the ChaCha20 cipher with the OpenSSL library. If an attacker manages to exhaust the heap space, this error is not detected and may lead to libssh using a partially initialized cipher context. This occurs because the OpenSSL error code returned aliases with the SSH_OK code, resulting in libssh not properly detecting the error returned by the OpenSSL library. This issue can lead to undefined behavior, including compromised data confidentiality and integrity or crashes.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:HAttack ComplexityHigh
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:HConfidentialityHigh
I:HIntegrityHigh
A:HAvailabilityHigh
Weaknesses
Affected Products
Red Hat Inc.
commercial·USaka Red Hat
Novell Inc.
commercial·US
Fedora Project
oss-project·USaka fedora
libssh
oss-projectaka libssh2 (related, sometimes confused)
ООО «Ред Софт»
commercial·RUaka red soft
and 16 more affected products View all →
Exploitability
Official Patch Available
References
https://access.redhat.com/errata/RHSA-2025:23483
access.redhat.com
https://access.redhat.com/errata/RHSA-2025:23484
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:0427
access.redhat.com
and 26 more references View all →
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