CVE-2025-68160
January 27, 2026
Issue summary: Writing large, newline-free data into a BIO chain using the
line-buffering filter where the next BIO performs short writes can trigger
a heap-based out-of-bounds write.
Impact summary: This out-of-bounds write can cause memory corruption which
typically results in a crash, leading to Denial of Service for an application.
The line-buffering BIO filter (BIO_f_linebuffer) is not used by default in
TLS/SSL data paths. In OpenSSL command-line applications, it is typically
only pushed onto stdout/stderr on VMS systems. Third-party applications that
explicitly use this filter with a BIO chain that can short-write and that
write large, newline-free data influenced by an attacker would be affected.
However, the circumstances where this could happen are unlikely to be under
attacker control, and BIO_f_linebuffer is unlikely to be handling non-curated
data controlled by an attacker. For that reason the issue was assessed as
Low severity.
The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue,
as the BIO implementation is outside the OpenSSL FIPS module boundary.
OpenSSL 3.6, 3.5, 3.4, 3.3, 3.0, 1.1.1 and 1.0.2 are vulnerable to this issue.
Affected Packages
https://github.com/openssl/openssl.git (GITHUB):
Affected version(s) >=openssl-3.4.0 <openssl-3.4.4Fix Suggestion:
Update to version openssl-3.4.4https://github.com/openssl/openssl.git (GITHUB):
Affected version(s) >=openssl-3.3.0 <openssl-3.3.6Fix Suggestion:
Update to version openssl-3.3.6https://github.com/openssl/openssl.git (GITHUB):
Affected version(s) =openssl-3.6.0 <openssl-3.6.1Fix Suggestion:
Update to version openssl-3.6.1https://github.com/openssl/openssl.git (GITHUB):
Affected version(s) >=openssl-3.5.0 <openssl-3.5.5Fix Suggestion:
Update to version openssl-3.5.5https://github.com/openssl/openssl.git (GITHUB):
Affected version(s) >=openssl-3.0.0 <openssl-3.0.19Fix Suggestion:
Update to version openssl-3.0.19Related ResourcesĀ (6)
Do you need more information?
Contact UsCVSS v4
Base Score:
5.7
Attack Vector
LOCAL
Attack Complexity
HIGH
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
NONE
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
4.7
Attack Vector
LOCAL
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Weakness Type (CWE)
Out-of-bounds Write
EPSS
Base Score:
0.01