CVE WatchJul 25, 2026

CVE-2026-66034

libssh2 through 1.11.1, fixed in commit a13bb6c, contains a missing bounds check vulnerability that allows a malicious SSH server to trigger

CVSS

7.5

High

EPSS

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KEV

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Exploit Today

0-100

Published: Jul 24, 2026 · Last modified: Jul 25, 2026 · CWE-125 · CWE-908

EPSS · 30d

Not enough EPSS history yet.

Technical description

libssh2 through 1.11.1, fixed in commit a13bb6c, contains a missing bounds check vulnerability that allows a malicious SSH server to trigger an arbitrary-length heap out-of-bounds read and a free of an uninitialized pointer via the publickey subsystem. In libssh2_publickey_list_fetch(), the version 1 response parser reads a server-controlled comment_len value and advances the parse pointer without verifying sufficient bytes remain in the buffer, causing the out-of-bounds read to leak heap pointers from adjacent allocations defeating ASLR, followed by heap allocator state corruption when the error cleanup path frees an uninitialized pointer from a non-zeroed realloc() region.

Official references

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——0Out-of-bounds Read (CWE-125) in BACnet packet parsing (`bacdt_datetime_to_tod`) in Loytec LIP-ME201C, L-INX, L-GATE, L-ROC, L-IOB, L-DALI, L-VIS and L-PAD through 8.4.18 on LINX-A64 allows an unauthenticated remote attacker to crash `linx_a64.exe` and ultimately reboot the device via a malformed BACnet TimeSynchronization or UTC-TimeSynchronization packet with an invalid month value. The same vulnerability affects multiple other Loytec products.1d CVE-2026-56391—

3.3%

——1GNU coreutils uniq is vulnerable to an out‑of‑bounds read due to incorrect handling of multibyte input when the -w (--check-chars) option is used. The find_field() function miscalculates the byte length of characters by repeatedly processing a fixed pointer instead of advancing through the input, resulting in an inflated length value. This incorrect length is later used in a memcmp operation, causing reads beyond the allocated buffer when processing crafted multibyte input. When running GNU coreutils uniq with attacker-provided arguments, this behavior leads to a crash and potential adjacent heap memory exposure. This issue has been fixed in the commit d64e35a8a4c0e4608321433e0d84d917e4e36371.1d CVE-2026-160028.2 HIG

17.3%

——5The affected product is vulnerable to an Out-of-bounds read, which may allow an attacker to crash the parsing process and cause a denial of service.1d