OSV-2025-491 Heap-buffer-overflow in libssl.soNUMBER
A heap-buffer-overflow in OpenSSL's SSL_CTX_set_cipher_list allows attackers to cause denial of service or potentially execute code via crafted inputs.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is OSV-2025-491?
OSV-2025-491 is a memory corruption vulnerability in sudoers, published on 27 Jun 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=427814448
Crash type: Heap-buffer-overflow READ 5
Crash state:
libssl.soNUMBER
libssl.soNUMBER
SSL_CTX_set_cipher_list
Which versions are affected by OSV-2025-491?
1 open source package ship an affected version, including sudoers.
| Package | Affected | Fixed in |
|---|---|---|
sudoers OSS-Fuzz | All versions | None |
How do I fix OSV-2025-491?
No fix has been published for OSV-2025-491 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is OSV-2025-491 being exploited?
There is no known exploitation of OSV-2025-491 in the wild and no public exploit code.