#VU105451 Out-of-bounds write in musl libc - CVE-2025-26519

Vulnerability identifier: #VU105451

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2025-26519

CWE-ID: CWE-787

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
musl libc
Universal components / Libraries / Libraries used by multiple products

Vendor: GNU

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error when converting untrusted EUC-KR text to UTF-8. A remote attacker can pass specially crafted data to the application, trigger an out-of-bounds write and execute arbitrary code on the target system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

musl libc: 0.9.13 - 1.2.5

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External links
https://www.openwall.com/lists/oss-security/2025/02/13/2
https://www.openwall.com/lists/oss-security/2025/02/13/3
https://www.openwall.com/lists/oss-security/2025/02/13/4
https://www.openwall.com/lists/oss-security/2025/02/13/5
https://www.openwall.com/lists/oss-security/2025/02/14/5
https://www.openwall.com/lists/oss-security/2025/02/14/6
https://git.musl-libc.org/cgit/musl/commit/?id=c47ad25ea3b484e10326f933e927c0bc8cded3da
https://git.musl-libc.org/cgit/musl/commit/?id=e5adcd97b5196e29991b524237381a0202a60659
https://www.openwall.com/lists/oss-security/2025/02/13/2

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.