CVE-2025-15469 'openssl dgst' one-shot codepath silently truncates inputs >16MB
The openssl dgst tool silently truncates inputs over 16MB for one-shot algorithms, allowing attackers to modify trailing data without detection during signature verification.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-15469?
CVE-2025-15469 is a medium-severity vulnerability in Openssl Openssl, published on 27 Jan 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Issue summary: The 'openssl dgst' command-line tool silently truncates input data to 16MB when using one-shot signing algorithms and reports success instead of an error.
Impact summary: A user signing or verifying files larger than 16MB with one-shot algorithms (such as Ed25519, Ed448, or ML-DSA) may believe the entire file is authenticated while trailing data beyond 16MB remains unauthenticated.
When the 'openssl dgst' command is used with algorithms that only support one-shot signing (Ed25519, Ed448, ML-DSA-44, ML-DSA-65, ML-DSA-87), the input is buffered with a 16MB limit. If the input exceeds this limit, the tool silently truncates to the first 16MB and continues without signaling an error, contrary to what the documentation states. This creates an integrity gap where trailing bytes can be modified without detection if both signing and verification are performed using the same affected codepath.
The issue affects only the command-line tool behavior. Verifiers that process the full message using library APIs will reject the signature, so the risk primarily affects workflows that both sign and verify with the affected 'openssl dgst' command. Streaming digest algorithms for 'openssl dgst' and library users are unaffected.
The FIPS modules in 3.5 and 3.6 are not affected by this issue, as the command-line tools are outside the OpenSSL FIPS module boundary.
OpenSSL 3.5 and 3.6 are vulnerable to this issue.
OpenSSL 3.4, 3.3, 3.0, 1.1.1 and 1.0.2 are not affected by this issue.
Weakness: CWE-347
Which versions are affected by CVE-2025-15469?
It affects 1 product.
Products include Openssl Openssl.
How do I fix CVE-2025-15469?
Apply the vendor's patch.
Is CVE-2025-15469 being exploited?
There is no known exploitation of CVE-2025-15469 in the wild and no public exploit code.
Other vulnerabilities in Openssl Openssl
Sources
Also known as ALPINE-CVE-2025-15469, BELL-CVE-2025-15469, CLEANSTART-2026-ZX69358, DEBIAN-CVE-2025-15469, GHSA-v2vr-926q-29fr, JLSEC-2026-258 and 2 more.