CVE-2026-66033

Katalog CVE

CVSS 7.5 · High EPSS 0,58%

Kerentanan Out-of-bounds Read pada libssh2. Skor CVSS 3.1 7.5 (High) menurut vulncheck.com.

Deskripsi (NVD)

libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2_cipher_crypt() function in src/openssl.c that allows a malicious SSH server to crash any connecting client by negotiating AES-GCM ciphers during handshake. Attackers can exploit the underflow in the expression computing blocksize minus aadlen minus authentication tag length to trigger an out-of-bounds read and a memcpy call with a near-SIZE_MAX length argument, causing immediate process crash before any authentication occurs.

Rincian

Terbit di NVD

24 Juli 2026

Terakhir diubah

30 Juli 2026

Status NVD

Analyzed

CVSS 3.1

7.5 (High), sumber vulncheck.com
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H · uraikan di kalkulator

Jenis kelemahan (CWE)

CWE-125: Out-of-bounds Read
CWE-191: Integer Underflow (Wrap or Wraparound)

EPSS (30 hari)

0,58% peluang dieksploitasi; lebih tinggi dari 46,3% CVE lain

Produk dan versi terdampak

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

• https://github.com/libssh2/libssh2/commit/a2ed82d40964bbc0d64cd717aa0a5a892117d2e6 patch
• https://github.com/libssh2/libssh2/pull/2401 issue tracking · patch
• https://www.vulncheck.com/advisories/libssh2-integer-underflow-dos-via-aes-gcm-cipher-negotiation patch · advisory pihak ketiga