CVE-2025-69419 Out of bounds write in PKCS12_get_friendlyname() UTF-8 conversion

What is CVE-2025-69419?

CVE-2025-69419 is a high-severity memory corruption vulnerability in Openssl Openssl, published on 27 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Issue summary: Calling PKCS12_get_friendlyname() function on a maliciously crafted PKCS#12 file with a BMPString (UTF-16BE) friendly name containing non-ASCII BMP code point can trigger a one byte write before the allocated buffer.

Impact summary: The out-of-bounds write can cause a memory corruption which can have various consequences including a Denial of Service.

The OPENSSL_uni2utf8() function performs a two-pass conversion of a PKCS#12 BMPString (UTF-16BE) to UTF-8. In the second pass, when emitting UTF-8 bytes, the helper function bmp_to_utf8() incorrectly forwards the remaining UTF-16 source byte count as the destination buffer capacity to UTF8_putc(). For BMP code points above U+07FF, UTF-8 requires three bytes, but the forwarded capacity can be just two bytes. UTF8_putc() then returns -1, and this negative value is added to the output length without validation, causing the length to become negative. The subsequent trailing NUL byte is then written at a negative offset, causing write outside of heap allocated buffer.

The vulnerability is reachable via the public PKCS12_get_friendlyname() API when parsing attacker-controlled PKCS#12 files. While PKCS12_parse() uses a different code path that avoids this issue, PKCS12_get_friendlyname() directly invokes the vulnerable function. Exploitation requires an attacker to provide a malicious PKCS#12 file to be parsed by the application and the attacker can just trigger a one zero byte write before the allocated buffer. For that reason the issue was assessed as Low severity according to our Security Policy.

The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the PKCS#12 implementation is outside the OpenSSL FIPS module boundary.

OpenSSL 3.6, 3.5, 3.4, 3.3, 3.0 and 1.1.1 are vulnerable to this issue.

OpenSSL 1.0.2 is not affected by this issue.

Weakness: CWE-787

Which versions are affected by CVE-2025-69419?

It affects 1 product.

Products include Openssl Openssl.

How do I fix CVE-2025-69419?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2025-69419 being exploited?

There is no known exploitation of CVE-2025-69419 in the wild and no public exploit code.

Public exploit code: 1 proofs of concept on GitHub.

Other vulnerabilities in Openssl Openssl

• CVE-2009-3245 Null dereference in n/a Critical 10.0
• CVE-2006-3738 Memory corruption in n/a Critical 10.0
• CVE-2026-63073 Untrusted Sender DN Used as Format String in CMP Response Validation Critical 9.8
• CVE-2016-6309 Use after free in n/a Critical 9.8
• CVE-2016-0799 Integer overflow in n/a Critical 9.8

All Openssl Openssl vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as ALPINE-CVE-2025-69419, ALSA-2026:19187, ALSA-2026:3042, ALSA-2026:4472, AZL-75290, AZL-75786 and 41 more.